Initial commit

19 files changed, 3792 insertions, 0 deletions

diff --git a/noao/imred/argus/Revisions b/noao/imred/argus/Revisions
new file mode 100644
index 00000000..55828da5
--- /dev/null
+++ b/noao/imred/argus/Revisions
@@ -0,0 +1,60 @@
+.help revisions Jul91 noao.imred.argus
+.nf
+imred$argus/doc/doargus.hlp
+    Fixed minor formating problem.  (4/22/99, Valdes)
+
+imred$argus/doc/dohdydra.hlp
+imred$argus/doc/dohdydra.ms
+    Updated for change where if both crval and cdelt are INDEF then the
+    automatic identification is not done.  (5/2/96, Valdes)
+
+imred$argus/demos/mkdoargus.cl
+    Made the ARTDATA package parameters explicit (4/15/97, Valdes)
+
+imred$argus/argus.cl
+    Increased the minimum min_lenuserarea from 40000 to 100000.
+    (7/31/96, Valdes)
+
+imred$argus/doargus.cl
+imred$argus/doargus.par
+imred$argus/params.par
+imred$argus/doc/doargus.hlp
+imred$argus/doc/doargus.ms
+    Added crval/cdelt parameters used in new version with automatic arc
+    line identification.  (4/5/96, Valdes)
+
+imred$argus/doc/doargus.hlp
+imred$argus/doc/doargus.ms
+    Describes the new header option for the aperture identification table.
+    (7/25/95, Valdes)
+
+imred$argus/argus.cl
+imred$argus/doargus.cl
+imred$argus/doargus.par
+imred$argus/doc/doargus.hlp
+imred$argus/doc/doargus.ms
+imred$argus/demos/xgdoargus.dat
+    Added sky alignment option.  (7/19/95, Valdes)
+
+imred$argus/argus.cl
+imred$argus/argus.men
+    Added APSCATTER to the package.  (6/30/95, Valdes)
+
+=======
+V2.10.4
+=======
+
+imred$argus/argus.cl
+    Renamed the fiber response task to fibresponse. (12/31/94, Valdes)
+
+imred$argus/argus.cl
+    The task was incorrectly defined as being in the logical directory
+    msred instead of specred.  (8/24/92, Valdes)
+
+=======
+V2.10.1
+=======
+
+imred/argus/*
+    Installed (7/24/91, Valdes)
+.endhelp
diff --git a/noao/imred/argus/argus.cl b/noao/imred/argus/argus.cl
new file mode 100644
index 00000000..66e8949e
--- /dev/null
+++ b/noao/imred/argus/argus.cl
@@ -0,0 +1,82 @@
+#{ ARGUS package definition
+
+proto		# bscale
+
+s1 = envget ("min_lenuserarea")
+if (s1 == "")
+    reset min_lenuserarea = 100000
+else if (int (s1) < 100000)
+    reset min_lenuserarea = 100000
+
+# Define ARGUS package
+package argus
+
+# Package script tasks
+task	doargus		= "argus$doargus.cl"
+task	params		= "argus$params.par"
+
+# Fiber reduction script tasks
+task	proc		= "srcfibers$proc.cl"
+task	fibresponse	= "srcfibers$fibresponse.cl"
+task	arcrefs		= "srcfibers$arcrefs.cl"
+task	doarcs		= "srcfibers$doarcs.cl"
+task	doalign		= "srcfibers$doalign.cl"
+task	skysub		= "srcfibers$skysub.cl"
+task	batch		= "srcfibers$batch.cl"
+task	listonly	= "srcfibers$listonly.cl"
+task	getspec		= "srcfibers$getspec.cl"
+
+task	msresp1d	= "specred$msresp1d.cl"
+
+# Demos
+set	demos		= "argus$demos/"
+task	demos		= "demos$demos.cl"
+task	mkfibers	= "srcfibers$mkfibers.cl"
+
+# Onedspec tasks
+task	autoidentify,
+	continuum,
+	dispcor,
+	dopcor,
+	identify,
+	refspectra,
+	reidentify,
+	sapertures,
+	sarith,
+	sflip,
+	slist,
+	specplot,
+	specshift,
+	splot		= "onedspec$x_onedspec.e"
+task	scombine	= "onedspec$scombine/x_scombine.e"
+task	aidpars		= "onedspec$aidpars.par"
+task	bplot		= "onedspec$bplot.cl"
+task	scopy		= "onedspec$scopy.cl"
+task	dispcor1	= "onedspec$dispcor1.par"
+
+# Apextract tasks
+task	apall,
+	apedit,
+	apfind,
+	aprecenter,
+	apresize,
+	apscatter,
+	apsum,
+	aptrace		= "apextract$x_apextract.e"
+task	apdefault	= "apextract$apdefault.par"
+task	apparams	= "apextract$apparams.par"
+task	apall1		= "apextract$apall1.par"
+task	apscript	= "srcfibers$x_apextract.e"
+task	apscat1		= "apextract$apscat1.par"
+task	apscat2		= "apextract$apscat2.par"
+
+# Astutil tasks
+task	setairmass,
+	setjd		= "astutil$x_astutil.e"
+
+# Hide tasks from the user
+hidetask apparams, apall1, apscript, apscat1, apscat2, dispcor1, mkfibers
+hidetask params, proc, batch, arcrefs, doarcs, listonly, fibresponse, getspec
+hidetask doalign
+
+clbye()
diff --git a/noao/imred/argus/argus.dat b/noao/imred/argus/argus.dat
new file mode 100644
index 00000000..6caa8ccd
--- /dev/null
+++ b/noao/imred/argus/argus.dat
@@ -0,0 +1,48 @@
+1 1
+2 0
+3 1
+4 0
+5 1
+6 0
+7 1
+8 0
+9 1
+10 0
+11 1
+12 0
+13 1
+14 0
+15 1
+16 0
+17 1
+18 0
+19 1
+20 0
+21 1
+22 0
+23 1
+24 0
+25 1
+26 0
+27 1
+28 0
+29 1
+30 0
+31 1
+32 0
+33 1
+34 0
+35 1
+36 0
+37 1
+38 0
+39 1
+40 0
+41 1
+42 0
+43 1
+44 0
+45 1
+46 0
+47 1
+48 0
diff --git a/noao/imred/argus/argus.hd b/noao/imred/argus/argus.hd
new file mode 100644
index 00000000..a3fb1064
--- /dev/null
+++ b/noao/imred/argus/argus.hd
@@ -0,0 +1,7 @@
+# Help directory for the ARGUS package.
+
+$doc		 = "./doc/"
+
+doargus		hlp=doc$doargus.hlp
+
+revisions	sys=Revisions
diff --git a/noao/imred/argus/argus.men b/noao/imred/argus/argus.men
new file mode 100644
index 00000000..d5769d30
--- /dev/null
+++ b/noao/imred/argus/argus.men
@@ -0,0 +1,32 @@
+          apall - Extract 1D spectra (all parameters in one task)
+      apdefault - Set the default aperture parameters
+         apedit - Edit apertures interactively
+	 apfind - Automatically find spectra and define apertures
+     aprecenter - Recenter apertures
+       apresize - Resize apertures
+      apscatter - Fit and remove scattered light
+          apsum - Extract 1D spectra
+	aptrace - Trace positions of spectra
+
+          bplot - Batch plots of spectra
+      continuum - Fit the continuum in spectra
+        dispcor - Dispersion correct spectra
+	 dopcor - Doppler correct spectra
+       identify - Identify features in spectrum for dispersion solution
+       msresp1d - Create 1D response spectra from flat field and sky spectra
+     refspectra - Assign wavelength reference spectra to other spectra
+     reidentify - Automatically identify features in spectra
+     sapertures - Set or change aperture header information
+	 sarith - Spectrum arithmetic
+       scombine - Combine spectra having different wavelength ranges
+          scopy - Select and copy apertures in different spectral formats
+     setairmass - Compute effective airmass and middle UT for an exposure
+          setjd - Compute and set Julian dates in images
+	  sflip - Flip data and/or dispersion coordinates in spectra
+          slist - List spectrum header parameters
+       specplot - Stack and plot multiple spectra
+      specshift - Shift spectral dispersion coordinate systems
+          splot - Preliminary spectral plot/analysis
+
+        doargus - Process ARGUS spectra
+	  demos - Demonstrations and tests
diff --git a/noao/imred/argus/argus.par b/noao/imred/argus/argus.par
new file mode 100644
index 00000000..c2c381a5
--- /dev/null
+++ b/noao/imred/argus/argus.par
@@ -0,0 +1,13 @@
+# ARGUS parameter file
+observatory,s,h,"observatory",,,Observatory of data
+interp,s,h,"poly5","nearest|linear|poly3|poly5|spline3|sinc",,Interpolation type
+dispaxis,i,h,2,1,3,Image axis for 2D/3D images
+nsum,s,h,"1",,,"Number of lines/columns/bands to sum for 2D/3D images
+"
+database,f,h,"database",,,Database
+verbose,b,h,no,,,Verbose output?
+logfile,s,h,"logfile",,,Log file
+plotfile,s,h,"",,,"Plot file
+"
+records,s,h,""
+version,s,h,"ARGUS V1: January 1992"
diff --git a/noao/imred/argus/demos/demos.cl b/noao/imred/argus/demos/demos.cl
new file mode 100644
index 00000000..5b065c51
--- /dev/null
+++ b/noao/imred/argus/demos/demos.cl
@@ -0,0 +1,18 @@
+# DEMOS -- Run specified demo provided a demo file exists.
+
+procedure demos (demoname)
+
+file	demoname	{prompt="Demo name"}
+
+begin
+	file	demo, demofile
+
+	if ($nargs == 0 && mode != "h")
+	    type ("demos$demos.men")
+	demo = demoname
+	demofile = "demos$" // demo // ".cl"
+	if (access (demofile))
+	    cl (< demofile)
+	else
+	    error (1, "Unknown demo " // demo)
+end
diff --git a/noao/imred/argus/demos/demos.men b/noao/imred/argus/demos/demos.men
new file mode 100644
index 00000000..ee467bdf
--- /dev/null
+++ b/noao/imred/argus/demos/demos.men
@@ -0,0 +1,4 @@
+	MENU of ARGUS Demonstrations
+
+      doargus - Quick test of DOARGUS (small images, no comments, no delays)
+    mkdoargus - Make DOARGUS test data (12 fibers, 100x256)
diff --git a/noao/imred/argus/demos/demos.par b/noao/imred/argus/demos/demos.par
new file mode 100644
index 00000000..4181ed59
--- /dev/null
+++ b/noao/imred/argus/demos/demos.par
@@ -0,0 +1,2 @@
+demoname,f,a,"",,,"Demo name"
+mode,s,h,"ql",,,
diff --git a/noao/imred/argus/demos/doargus.cl b/noao/imred/argus/demos/doargus.cl
new file mode 100644
index 00000000..51e7f0d9
--- /dev/null
+++ b/noao/imred/argus/demos/doargus.cl
@@ -0,0 +1,13 @@
+# Create demo data if needed.
+
+cl (< "demos$mkdoargus.cl")
+
+delete ("demologfile,demoplotfile", verify=no, >& "dev$null")
+
+unlearn doargus params
+
+# Execute playback.
+if (substr (envget("stdgraph"), 1, 6) == "xgterm")
+    stty (playback="demos$xgdoargus.dat", nlines=24, verify=no, delay=0)
+else
+    error (1, "Playback for current terminal type not available")
diff --git a/noao/imred/argus/demos/header.dat b/noao/imred/argus/demos/header.dat
new file mode 100644
index 00000000..2e104ae7
--- /dev/null
+++ b/noao/imred/argus/demos/header.dat
@@ -0,0 +1,36 @@
+OBJECT  = 'V640Mon 4500      '  /  object name
+OBSERVAT= 'CTIO              '  /  observatory
+OBSERVER= 'Massey            '  /  observers
+COMMENTS= 'Final New Ice     '  /  comments
+EXPTIME =                1200.  /  actual integration time
+DARKTIME=                1200.  /  total elapsed time
+IMAGETYP= 'object            '  /  object, dark, bias, etc.
+DATE-OBS= '26/11/91          '  /  date (dd/mm/yy) of obs.
+UT      = '12:19:55.00       '  /  universal time
+ST      = '09:13:15.00       '  /  sidereal time
+RA      = '06:37:02.00       '  /  right ascension
+DEC     = '06:08:52.00       '  /  declination
+EPOCH   =               1991.9  /  epoch of ra and dec
+ZD      = '44.580            '  /  zenith distance
+TELESCOP= 'kpcdf             '  /  telescope name
+DETECTOR= 'te1k              '  /  detector
+PREFLASH=                    0  /  preflash time, seconds
+GAIN    =                  5.4  /  gain, electrons per adu
+DWELL   =                    5  /  sample integration time
+RDNOISE =                  3.5  /  read noise, electrons per adu
+DELAY0  =                    0  /  time delay after each pixel
+DELAY1  =                    0  /  time delay after each row
+CAMTEMP =                 -111  /  camera temperature
+DEWTEMP =                 -183  /  dewar temperature
+CCDSEC  = '[97:134,2:1023]'     /  orientation to full frame
+ORIGSEC = '[1:1024,1:1024]   '  /  original size  full frame
+CCDSUM  = '1 1               '  /  on chip summation
+INSTRUME= 'IRAF/ARTDATA      '  /  instrument
+APERTURE= '250micron slit    '  /  aperture
+TVFILT  = '4-96              '  /  tv filter
+DISPAXIS= '2                 '  /  dispersion axis
+GRATPOS =               4624.3  /  grating position
+TRIM    = 'Nov 26  5:44 Trim data section is [23:60,2:1023]'
+OVERSCAN= 'Nov 26  5:44 Overscan section is [103:133,2:1023] with mean=611.1
+ZEROCOR = 'Nov 26  5:44 Zero level correction image is Zerof'
+CCDPROC = 'Nov 26  5:44 CCD processing done'
diff --git a/noao/imred/argus/demos/mkdoargus.cl b/noao/imred/argus/demos/mkdoargus.cl
new file mode 100644
index 00000000..39c94db0
--- /dev/null
+++ b/noao/imred/argus/demos/mkdoargus.cl
@@ -0,0 +1,22 @@
+# Create demo data if needed.
+
+artdata
+artdata.nxc = 5
+artdata.nyc = 5
+artdata.nxsub = 10
+artdata.nysub = 10
+artdata.nxgsub = 5
+artdata.nygsub = 5
+artdata.dynrange = 100000.
+artdata.psfrange = 10.
+artdata.ranbuf = 0
+
+mkfibers ("demoobj", type="object", fibers="demos$mkdoargus.dat",
+    title="Argus artificial image", header="demos$header.dat",
+    ncols=100, nlines=256, wstart=5786., wend=7362., seed=1)
+mkfibers ("demoflat", type="flat", fibers="demos$mkdoargus.dat",
+    title="Argus artificial image", header="demos$header.dat",
+    ncols=100, nlines=256, wstart=5786., wend=7362., seed=2)
+mkfibers ("demoarc", type="henear", fibers="demos$mkdoargus.dat",
+    title="Argus artificial image", header="demos$header.dat",
+    ncols=100, nlines=256, wstart=5786., wend=7362., seed=3)
diff --git a/noao/imred/argus/demos/mkdoargus.dat b/noao/imred/argus/demos/mkdoargus.dat
new file mode 100644
index 00000000..8f9311c0
--- /dev/null
+++ b/noao/imred/argus/demos/mkdoargus.dat
@@ -0,0 +1,13 @@
+ 1 1 1.096679 gauss 2.7 0 86.801 0.002
+ 2 0 1.164292 gauss 2.7 0 81.093 0.002
+ 3 1 0.457727 gauss 2.7 0 74.824 0.002
+ 4 0 1.269284 gauss 2.7 0 68.719 0.002
+ 5 1 1.309297 gauss 2.7 0 62.536 0.002
+ 7 1 1.283618 gauss 2.7 0 50.218 0.002
+ 8 0 0.687173 gauss 2.7 0 43.963 0.002
+ 9 1 1.175850 gauss 2.7 0 38.0091 0.002
+10 0 0.757532 gauss 2.7 0 31.9606 0.002
+11 1 0.939866 gauss 2.7 0 25.1000 0.002
+12 0 1.015546 gauss 2.7 0 19.5097 0.002
+13 1 0.372036 gauss 2.7 0 13.5889 0.002
+14 0 1.065080 gauss 2.7 0 07.4535 0.002
diff --git a/noao/imred/argus/demos/xgdoargus.dat b/noao/imred/argus/demos/xgdoargus.dat
new file mode 100644
index 00000000..e3fb9dfd
--- /dev/null
+++ b/noao/imred/argus/demos/xgdoargus.dat
@@ -0,0 +1,76 @@
+\O=NOAO/IRAF IRAFX valdes@puppis Mon 14:58:37 15-Nov-93
+\T=xgterm
+\G=xgterm
+epar\sargus\n
+\r
+\r
+\r
+\r
+\r
+y\r
+demologfile\r
+demoplotfile\r
+^Z
+epar\sdoargus\n
+demoobj\r
+demoflat\r
+demoflat\r
+\r
+demoarc\r
+\r
+\r
+rdnoise\r
+gain\r
+\r
+13\r
+4\r
+5\r
+7\r
+\r
+6600\r
+6.1\r
+\r
+\r
+\r
+\r
+\r
+\r
+n\r
+\r
+\r
+\r
+\r
+\r
+y\r
+^Z
+doargus\sredo+\n
+\n
+\n
+\n
+q/<-5\s\s\s\s/=(.\s=\r
+\r
+\r
+q/<-5\s\s\s\s/=(.\s=\r
+N\r
+j/<-5\s\s\s\s/=(.\s=\r
+q/<-5\s\s\s\s/=(.\s=\r
+f/<-5\s\s\s\s/=(.\s=\r
+l/<-5\s\s\s\s/=(.\s=\r
+q/<-5\s\s\s\s/=(.\s=\r
+q/<-5\s\s\s\s/=(.\s=\r
+n\n
+y\n
+f/<-5\s\s\s\s/=(.\s=\r
+l/<-5\s\s\s\s/=(.\s=\r
+q/<-5\s\s\s\s/=(.\s=\r
+q/<-5\s\s\s\s/=(.\s=\r
+N\n
+n\n
+\n
+q/<-5\s\s\s\s/=(.\s=\r
+\n
+\n
+\n
+#/<-5\s\s\s\s/=(.\s=\r 3\r
+#/<-5\s\s\s\s/=(.\s=\r 14\r
+q/<-5\s\s\s\s/=(.\s=\r
diff --git a/noao/imred/argus/doargus.cl b/noao/imred/argus/doargus.cl
new file mode 100644
index 00000000..a34e61c8
--- /dev/null
+++ b/noao/imred/argus/doargus.cl
@@ -0,0 +1,71 @@
+# DOARGUS -- Process ARGUS spectra from 2D to wavelength calibrated 1D.
+#
+# The task PROC does all of the interactive work and BATCH does the
+# background work.  This procedure is organized this way to minimize the
+# dictionary space when the background task is submitted.
+
+procedure doargus (objects)
+
+string	objects = ""		{prompt="List of object spectra"}
+
+file	apref = ""		{prompt="Aperture reference spectrum"}
+file	flat = ""		{prompt="Flat field spectrum"}
+file	throughput = ""		{prompt="Throughput file or image (optional)"}
+string	arcs1 = ""		{prompt="List of arc spectra"}
+string	arcs2 = ""		{prompt="List of shift arc spectra"}
+file	arctable = ""		{prompt="Arc assignment table (optional)\n"}
+
+string	readnoise = "0."	{prompt="Read out noise sigma (photons)"}
+string	gain = "1."		{prompt="Photon gain (photons/data number)"}
+real	datamax = INDEF		{prompt="Max data value / cosmic ray threshold"}
+int	fibers = 48		{prompt="Number of fibers"}
+real	width = 6.		{prompt="Width of profiles (pixels)"}
+real	minsep = 8.	{prompt="Minimum separation between fibers (pixels)"}
+real	maxsep = 10.	{prompt="Maximum separation between fibers (pixels)"}
+file	apidtable = ""		{prompt="Aperture identifications"}
+string	crval = "INDEF"		{prompt="Approximate central wavelength"}
+string	cdelt = "INDEF"		{prompt="Approximate dispersion"}
+string	objaps = ""		{prompt="Object apertures"}
+string	skyaps = "2x2"		{prompt="Sky apertures"}
+string	objbeams = ""		{prompt="Object beam numbers"}
+string	skybeams = ""		{prompt="Sky beam numbers\n"}
+
+bool	scattered = no		{prompt="Subtract scattered light?"}
+bool	fitflat = yes		{prompt="Fit and ratio flat field spectrum?"}
+bool	clean = yes		{prompt="Detect and replace bad pixels?"}
+bool	dispcor = yes		{prompt="Dispersion correct spectra?"}
+bool	skyalign = no		{prompt="Align sky lines?"}
+bool	skysubtract = yes	{prompt="Subtract sky?"}
+bool	skyedit = yes		{prompt="Edit the sky spectra?"}
+bool	saveskys = yes		{prompt="Save sky spectra?"}
+bool	splot = no		{prompt="Plot the final spectrum?"}
+bool	redo = no		{prompt="Redo operations if previously done?"}
+bool	update = yes		{prompt="Update spectra if cal data changes?"}
+bool	batch = no		{prompt="Extract objects in batch?"}
+bool	listonly = no		{prompt="List steps but don't process?\n"}
+
+pset	params = ""		{prompt="Algorithm parameters"}
+
+begin
+	apscript.readnoise = readnoise
+	apscript.gain = gain
+	apscript.nfind = fibers
+	apscript.width = width
+	apscript.t_width = width
+	apscript.minsep = minsep
+	apscript.maxsep = maxsep
+	apscript.radius = minsep
+	apscript.clean = clean
+	proc.datamax = datamax
+
+	proc (objects, apref, flat, throughput, arcs1, arcs2, "",
+	    arctable, fibers, apidtable, crval, cdelt, objaps, skyaps, "",
+	    objbeams, skybeams, "", scattered, fitflat, no, no, no, no,
+	    clean, dispcor, no, skyalign, skysubtract, skyedit, saveskys,
+	    splot, redo, update, batch, listonly)
+
+	if (proc.dobatch) {
+	    print ("-- Do remaining spectra as a batch job --")
+	    print ("batch&batch") | cl
+	}
+end
diff --git a/noao/imred/argus/doargus.par b/noao/imred/argus/doargus.par
new file mode 100644
index 00000000..fb55934c
--- /dev/null
+++ b/noao/imred/argus/doargus.par
@@ -0,0 +1,39 @@
+objects,s,a,"",,,"List of object spectra"
+apref,f,h,"",,,"Aperture reference spectrum"
+flat,f,h,"",,,"Flat field spectrum"
+throughput,f,h,"",,,"Throughput file or image (optional)"
+arcs1,s,h,"",,,"List of arc spectra"
+arcs2,s,h,"",,,"List of shift arc spectra"
+arctable,f,h,"",,,"Arc assignment table (optional)
+"
+readnoise,s,h,"0.",,,"Read out noise sigma (photons)"
+gain,s,h,"1.",,,"Photon gain (photons/data number)"
+datamax,r,h,INDEF,,,"Max data value / cosmic ray threshold"
+fibers,i,h,48,,,"Number of fibers"
+width,r,h,6.,,,"Width of profiles (pixels)"
+minsep,r,h,8.,,,"Minimum separation between fibers (pixels)"
+maxsep,r,h,10.,,,"Maximum separation between fibers (pixels)"
+apidtable,f,h,"",,,"Aperture identifications"
+crval,s,h,INDEF,,,"Approximate central wavelength"
+cdelt,s,h,INDEF,,,"Approximate dispersion"
+objaps,s,h,"",,,"Object apertures"
+skyaps,s,h,"2x2",,,"Sky apertures"
+objbeams,s,h,"",,,"Object beam numbers"
+skybeams,s,h,"",,,"Sky beam numbers
+"
+scattered,b,h,no,,,"Subtract scattered light?"
+fitflat,b,h,yes,,,"Fit and ratio flat field spectrum?"
+clean,b,h,yes,,,"Detect and replace bad pixels?"
+dispcor,b,h,yes,,,"Dispersion correct spectra?"
+skyalign,b,h,no,,,"Align sky lines?"
+skysubtract,b,h,yes,,,"Subtract sky?"
+skyedit,b,h,yes,,,"Edit the sky spectra?"
+saveskys,b,h,yes,,,"Save sky spectra?"
+splot,b,h,no,,,"Plot the final spectrum?"
+redo,b,h,no,,,"Redo operations if previously done?"
+update,b,h,yes,,,"Update spectra if cal data changes?"
+batch,b,h,no,,,"Extract objects in batch?"
+listonly,b,h,no,,,"List steps but don\'t process?
+"
+params,pset,h,"",,,"Algorithm parameters"
+mode,s,h,"ql",,,
diff --git a/noao/imred/argus/doc/doargus.hlp b/noao/imred/argus/doc/doargus.hlp
new file mode 100644
index 00000000..0ffc4bb6
--- /dev/null
+++ b/noao/imred/argus/doc/doargus.hlp
@@ -0,0 +1,1464 @@
+.help doargus Jul95 noao.imred.argus
+.ih
+NAME
+doargus -- Argus data reduction task
+.ih
+USAGE
+doargus objects
+.ih
+SUMMARY
+The \fBdoargus\fR reduction task is specialized for scattered light
+subtraction, extraction, flat fielding, fiber throughput correction,
+wavelength calibration, and sky subtraction of \fIArgus\fR fiber spectra.
+It is a command language script which collects and combines the functions
+and parameters of many general purpose tasks to provide a single complete
+data reduction path.  The task provides a degree of guidance, automation,
+and record keeping necessary when dealing with the large amount of data
+generated by this multifiber instrument.
+.ih
+PARAMETERS
+.ls objects
+List of object spectra to be processed.  Previously processed spectra are
+ignored unless the \fIredo\fR flag is set or the \fIupdate\fR flag is set and
+dependent calibration data has changed.  Extracted spectra are ignored.
+.le
+.ls apref = ""
+Aperture reference spectrum.  This spectrum is used to define the basic
+extraction apertures and is typically a flat field spectrum.
+.le
+.ls flat = "" (optional)
+Flat field spectrum.  If specified the one dimensional flat field spectra
+are extracted and used to make flat field calibrations.  If a separate
+throughput file or image is not specified the flat field is also used
+for computing a fiber throughput correction.
+.le
+.ls throughput = "" (optional)
+Throughput file or image.  If an image is specified, typically a blank sky
+observation, the total flux through each fiber is used to correct for fiber
+throughput.  If a file consisting of lines with the aperture number and
+relative throughput is specified then the fiber throughput will be
+corrected by those values.  If neither is specified but a flat field image
+is given it is used to compute the throughput.
+.le
+.ls arcs1 = "" (at least one if dispersion correcting)
+List of primary arc spectra.  These spectra are used to define the dispersion
+functions for each fiber apart from a possible zero point correction made
+with secondary shift spectra or arc calibration fibers in the object spectra.
+One fiber from the first spectrum is used to mark lines and set the dispersion
+function interactively and dispersion functions for all other fibers and
+arc spectra are derived from it.
+.le
+.ls arcs2 = "" (optional)
+List of optional shift arc spectra.  Features in these secondary observations
+are used to supply a wavelength zero point shift through the observing
+sequence.  One type of observation is dome lamps containing characteristic
+emission lines.
+.le
+.ls arctable = "" (optional) (refspectra)
+Table defining arc spectra to be assigned to object
+spectra (see \fBrefspectra\fR).  If not specified an assignment based
+on a header parameter, \fIparams.sort\fR, such as the observation time is made.
+.le
+
+.ls readnoise = "0." (apsum)
+Read out noise in photons.  This parameter defines the minimum noise
+sigma.  It is defined in terms of photons (or electrons) and scales
+to the data values through the gain parameter.  A image header keyword
+(case insensitive) may be specified to get the value from the image.
+.le
+.ls gain = "1." (apsum)
+Detector gain or conversion factor between photons/electrons and
+data values.  It is specified as the number of photons per data value.
+A image header keyword (case insensitive) may be specified to get the value
+from the image.
+.le
+.ls datamax = INDEF (apsum.saturation)
+The maximum data value which is not a cosmic ray.
+When cleaning cosmic rays and/or using variance weighted extraction
+very strong cosmic rays (pixel values much larger than the data) can
+cause these operations to behave poorly.  If a value other than INDEF
+is specified then all data pixels in excess of this value will be
+excluded and the algorithms will yield improved results.
+This applies only to the object spectra and not the flat field or arc
+spectra.  For more
+on this see the discussion of the saturation parameter in the
+\fBapextract\fR package.
+.le
+.ls fibers = 48 (apfind)
+Number of fibers.  This number is used during the automatic definition of
+the apertures from the aperture reference spectrum.  It is best if this
+reflects the actual number of fibers which may be found in the aperture
+reference image.  Note that Argus fibers which are unassigned will still
+contain enough light for identification and the aperture identification
+table will be used to eliminate the unassigned fibers.  The interactive
+review of the aperture assignments allows verification and adjustments
+to the automatic aperture definitions.
+.le
+.ls width = 6. (apedit)
+Approximate base full width of the fiber profiles.  This parameter is used
+for the profile centering algorithm.
+.le
+.ls minsep = 8. (apfind)
+Minimum separation between fibers.  Weaker spectra or noise within this
+distance of a stronger spectrum are rejected.
+.le
+.ls maxsep = 10. (apfind)
+Maximum separation between adjacent fibers.  This parameter
+is used to identify missing fibers.  If two adjacent spectra exceed this
+separation then it is assumed that a fiber is missing and the aperture
+identification assignments will be adjusted accordingly.
+.le
+.ls apidtable = "" (apfind)
+Aperture identification table.  This may be either a text file or an
+image.  A text file contains the fiber number, beam number defining object
+(1), sky (0), and arc (2) fibers, and a object title.  An image contains
+the keywords SLFIBnnn with string value consisting of the fiber number,
+beam number, optional right ascension and declination, and an object
+title.  Unassigned and broken fibers (beam of -1)
+should be included in this list since they will automatically be excluded.
+.le
+.ls crval = INDEF, cdelt = INDEF (autoidentify)
+These parameters specify an approximate central wavelength and dispersion.
+They may be specified as numerical values, INDEF, or image header keyword
+names whose values are to be used.
+If both these parameters are INDEF then the automatic identification will
+not be done.
+.le
+.ls objaps = "", skyaps = "2x2"
+List of object and sky aperture numbers.  These are used to identify
+object and sky
+apertures for sky subtraction.  Note sky apertures may be identified as
+both object and sky if one wants to subtract the mean sky from the
+individual sky spectra.  Because the fibers typically alternate
+sky and object the default is to define the sky apertures by their
+aperture numbers and select both object and sky fibers for sky subtraction.
+.le
+.ls objbeams = "", skybeams = ""
+List of object and sky beam numbers.
+The beam numbers are typically the same as the aperture numbers unless
+set in the \fIapidtable\fR.
+.le
+
+.ls scattered = no (apscatter)
+Smooth and subtracted scattered light from the object and flat field
+images.  This operation consists of fitting independent smooth functions
+across the dispersion using data outside the fiber apertures and then
+smoothing the individual fits along the dispersion.  The initial
+flat field, or if none is given the aperture reference image, are
+done interactively to allow setting the fitting parameters.  All
+subsequent subtractions use the same fitting parameters.
+.le
+.ls fitflat = yes (flat1d)
+Fit the composite flat field spectrum by a smooth function and divide each
+flat field spectrum by this function?  This operation removes the average
+spectral signature of the flat field lamp from the sensitivity correction to
+avoid modifying the object fluxes.
+.le
+.ls clean = yes (apsum)
+Detect and correct for bad pixels during extraction?  This is the same
+as the clean option in the \fBapextract\fR package.  If yes this also
+implies variance weighted extraction and requires reasonably good values
+for the readout noise and gain.  In addition the datamax parameters
+can be useful.
+.le
+.ls dispcor = yes
+Dispersion correct spectra?  Depending on the \fIparams.linearize\fR
+parameter this may either resample the spectra or insert a dispersion
+function in the image header.
+.le
+.ls skyalign = no
+Align sky lines?  If yes then for the first object spectrum you are asked
+to mark one or more sky lines to use for alignment.  Then these lines will
+be found in all spectra and an average zeropoint shift computed and applied
+to the dispersion solution to align these lines.  Note that this assumes
+the sky lines are seen in all fibers.
+.le
+.ls skysubtract = yes
+Subtract sky from the object spectra?  If yes the sky spectra are combined
+and subtracted from the object spectra as defined by the object and sky
+aperture/beam parameters.
+.le
+.ls skyedit = yes
+Overplot all the sky spectra and allow contaminated sky spectra to be
+deleted?
+.le
+.ls saveskys = yes
+Save the combined sky spectrum?  If no then the sky spectrum will be
+deleted after sky subtraction is completed.
+.le
+.ls splot = no
+Plot the final spectra with the task \fBsplot\fR?
+.le
+.ls redo = no
+Redo operations previously done?  If no then previously processed spectra
+in the objects list will not be processed (unless they need to be updated).
+.le
+.ls update = yes
+Update processing of previously processed spectra if aperture, flat
+field, or dispersion reference definitions are changed?
+.le
+.ls batch = no
+Process spectra as a background or batch job provided there are no interactive
+options (\fIskyedit\fR and \fIsplot\fR) selected.
+.le
+.ls listonly = no
+List processing steps but don't process?
+.le
+
+.ls params = "" (pset)
+Name of parameter set containing additional processing parameters.  The
+default is parameter set \fBparams\fR.  The parameter set may be examined
+and modified in the usual ways (typically with "epar params" or ":e params"
+from the parameter editor).  Note that using a different parameter file
+is not allowed.  The parameters are described below.
+.le
+
+.ce
+-- PACKAGE PARAMETERS
+
+Package parameters are those which generally apply to all task in the
+package.  This is also true of \fBdoargus\fR.
+.ls dispaxis = 2
+Default dispersion axis.  The dispersion axis is 1 for dispersion
+running along image lines and 2 for dispersion running along image
+columns.  If the image header parameter DISPAXIS is defined it has
+precedence over this parameter.  The default value defers to the
+package parameter of the same name.
+.le
+.ls observatory = "observatory"
+Observatory at which the spectra were obtained if not specified in the
+image header by the keyword OBSERVAT.  For Argus data the image headers
+identify the observatory as "kpno" so this parameter is not used.
+For data from other observatories this parameter may be used
+as describe in \fBobservatory\fR.
+.le
+.ls interp = "poly5" (nearest|linear|poly3|poly5|spline3|sinc)
+Spectrum interpolation type used when spectra are resampled.  The choices are:
+
+.nf
+	nearest - nearest neighbor
+	 linear - linear
+	  poly3 - 3rd order polynomial
+	  poly5 - 5th order polynomial
+	spline3 - cubic spline
+	   sinc - sinc function
+.fi
+.le
+.ls database = "database"
+Database (directory) used for storing aperture and dispersion information.
+.le
+.ls verbose = no
+Print verbose information available with various tasks.
+.le
+.ls logfile = "logfile", plotfile = ""
+Text and plot log files.  If a filename is not specified then no log is
+kept.  The plot file contains IRAF graphics metacode which may be examined
+in various ways such as with \fBgkimosaic\fR.
+.le
+.ls records = ""
+Dummy parameter to be ignored.
+.le
+.ls version = "ARGUS: ..."
+Version of the package.
+.le
+
+.ce
+PARAMS PARAMETERS
+
+The following parameters are part of the \fBparams\fR parameter set and
+define various algorithm parameters for \fBdoargus\fR.
+
+.ce
+--  GENERAL PARAMETERS --
+.ls line = INDEF, nsum = 10
+The dispersion line (line or column perpendicular to the dispersion
+axis) and number of adjacent lines (half before and half after unless
+at the end of the image) used in finding, recentering, resizing,
+editing, and tracing operations.  A line of INDEF selects the middle of the
+image along the dispersion axis.
+.le
+.ls order = "decreasing" (apfind)
+When assigning aperture identifications order the spectra "increasing"
+or "decreasing" with increasing pixel position (left-to-right or
+right-to-left in a cross-section plot of the image).
+.le
+.ls extras = no (apsum)
+Include extra information in the output spectra?  When cleaning or using
+variance weighting the cleaned and weighted spectra are recorded in the
+first 2D plane of a 3D image, the raw, simple sum spectra are recorded in
+the second plane, and the estimated sigmas are recorded in the third plane.
+.le
+
+.ce
+-- DEFAULT APERTURE LIMITS --
+.ls lower = -3., upper = 3. (apdefault)
+Default lower and upper aperture limits relative to the aperture center.
+These limits are used when the apertures are first found and may be
+resized automatically or interactively.
+.le
+
+.ce
+-- AUTOMATIC APERTURE RESIZING PARAMETERS --
+.ls ylevel = 0.05 (apresize)
+Data level at which to set aperture limits during automatic resizing.
+It is a fraction of the peak relative to a local background.
+.le
+
+.ce
+-- TRACE PARAMETERS --
+.ls t_step = 10 (aptrace)
+Step along the dispersion axis between determination of the spectrum
+positions.  Note the \fInsum\fR parameter is also used to enhance the
+signal-to-noise at each step.
+.le
+.ls t_function = "spline3", t_order = 3 (aptrace)
+Default trace fitting function and order.  The fitting function types are
+"chebyshev" polynomial, "legendre" polynomial, "spline1" linear spline, and
+"spline3" cubic spline.  The order refers to the number of
+terms in the polynomial functions or the number of spline pieces in the spline
+functions.
+.le
+.ls t_niterate = 1, t_low = 3., t_high = 3. (aptrace)
+Default number of rejection iterations and rejection sigma thresholds.
+.le
+
+.ce
+-- SCATTERED LIGHT PARAMETERS --
+.ls buffer = 1. (apscatter)
+Buffer distance from the aperture edges to be excluded in selecting the
+scattered light pixels to be used.
+.le
+.ls apscat1 = "" (apscatter)
+Fitting parameters across the dispersion.  This references an additional
+set of parameters for the ICFIT package.  The default is the "apscat1"
+parameter set.
+.le
+.ls apscat2 = "" (apscatter)
+Fitting parameters along the dispersion.  This references an additional
+set of parameters for the ICFIT package.  The default is the "apscat2"
+parameter set.
+.le
+
+.ce
+-- APERTURE EXTRACTION PARAMETERS --
+.ls weights = "none" (apsum)
+Type of extraction weighting.  Note that if the \fIclean\fR parameter is
+set then the weights used are "variance" regardless of the weights
+specified by this parameter.  The choices are:
+.ls "none"
+The pixels are summed without weights except for partial pixels at the
+ends.
+.le
+.ls "variance"
+The extraction is weighted by the variance based on the data values
+and a poisson/ccd model using the \fIgain\fR and \fIreadnoise\fR
+parameters.
+.le
+.le
+.ls pfit = "fit1d" (apsum) (fit1d|fit2d)
+Profile fitting algorithm for cleaning and variance weighted extractions.
+The default is generally appropriate for Argus data but users
+may try the other algorithm.  See \fBapprofiles\fR for further information.
+.le
+.ls lsigma = 3., usigma = 3. (apsum)
+Lower and upper rejection thresholds, given as a number of times the
+estimated sigma of a pixel, for cleaning.
+.le
+.ls nsubaps = 1 (apsum)
+During extraction it is possible to equally divide the apertures into
+this number of subapertures.
+.le
+
+.ce
+-- FLAT FIELD FUNCTION FITTING PARAMETERS --
+.ls f_interactive = yes (fit1d)
+Fit the composite one dimensional flat field spectrum interactively?
+This is used if \fIfitflat\fR is set and a two dimensional flat field
+spectrum is specified.
+.le
+.ls f_function = "spline3", f_order = 10 (fit1d)
+Function and order used to fit the composite one dimensional flat field
+spectrum.  The functions are "legendre", "chebyshev", "spline1", and
+"spline3".  The spline functions are linear and cubic splines with the
+order specifying the number of pieces.
+.le
+
+.ce
+-- ARC DISPERSION FUNCTION PARAMETERS --
+.ls threshold = 10. (autoidentify/identify/reidentify)
+In order for a feature center to be determined the range of pixel intensities
+around the feature must exceed this threshold.
+.le
+.ls coordlist = "linelists$ctiohenear.dat" (autoidentify/identify)
+Arc line list consisting of an ordered list of wavelengths.
+Some standard line lists are available in the directory "linelists$".
+.le
+.ls match = -3. (autoidentify/identify)
+The maximum difference for a match between the dispersion function prediction
+value and a wavelength in the coordinate list.
+.le
+.ls fwidth = 4. (autoidentify/identify)
+Approximate full base width (in pixels) of arc lines.
+.le
+.ls cradius = 10. (reidentify)
+Radius from previous position to reidentify arc line.
+.le
+.ls i_function = "chebyshev", i_order = 3 (autoidentify/identify)
+The default function and order to be fit to the arc wavelengths as a
+function of the pixel coordinate.  The functions choices are "chebyshev",
+"legendre", "spline1", or "spline3".
+.le
+.ls i_niterate = 2, i_low = 3.0, i_high = 3.0 (autoidentify/identify)
+Number of rejection iterations and sigma thresholds for rejecting arc
+lines from the dispersion function fits.
+.le
+.ls refit = yes (reidentify)
+Refit the dispersion function?  If yes and there is more than 1 line
+and a dispersion function was defined in the arc reference then a new
+dispersion function of the same type as in the reference image is fit
+using the new pixel positions.  Otherwise only a zero point shift is
+determined for the revised fitted coordinates without changing the
+form of the dispersion function.
+.le
+.ls addfeatures = no (reidentify)
+Add new features from a line list during each reidentification?
+This option can be used to compensate for lost features from the
+reference solution.  Care should be exercised that misidentified features
+are not introduced.
+.le
+
+.ce
+-- AUTOMATIC ARC ASSIGNMENT PARAMETERS --
+.ls select = "interp" (refspectra)
+Selection method for assigning wavelength calibration spectra.
+Note that an arc assignment table may be used to override the selection
+method and explicitly assign arc spectra to object spectra.
+The automatic selection methods are:
+.ls average
+Average two reference spectra without regard to any sort parameter.
+If only one reference spectrum is specified then it is assigned with a
+warning.  If more than two reference spectra are specified then only the
+first two are used and a warning is given.
+This option is used to assign two reference spectra, with equal weights,
+independent of any sorting parameter.
+.le
+.ls following
+Select the nearest following spectrum in the reference list based on the
+sorting parameter.  If there is no following spectrum use the nearest preceding
+spectrum.
+.le
+.ls interp
+Interpolate between the preceding and following spectra in the reference
+list based on the sorting parameter.  If there is no preceding and following
+spectrum use the nearest spectrum.  The interpolation is weighted by the
+relative distances of the sorting parameter.
+.le
+.ls match
+Match each input spectrum with the reference spectrum list in order.
+This overrides the reference aperture check.
+.le
+.ls nearest
+Select the nearest spectrum in the reference list based on the sorting
+parameter.
+.le
+.ls preceding
+Select the nearest preceding spectrum in the reference list based on the
+sorting parameter.  If there is no preceding spectrum use the nearest following
+spectrum.
+.le
+.le
+.ls sort = "jd", group = "ljd" (refspectra)
+Image header keywords to be used as the sorting parameter for selection
+based on order and to group spectra.
+A null string, "", or the word "none" may be use to disable the sorting
+or grouping parameters.
+The sorting parameter
+must be numeric but otherwise may be anything.  The grouping parameter
+may be a string or number and must simply be the same for all spectra within
+the same group (say a single night).
+Common sorting parameters are times or positions.
+In \fBdoargus\fR the Julian date (JD) and the local Julian day number (LJD)
+at the middle of the exposure are automatically computed from the universal
+time at the beginning of the exposure and the exposure time.  Also the
+parameter UTMIDDLE is computed.
+.le
+.ls time = no, timewrap = 17. (refspectra)
+Is the sorting parameter a 24 hour time?  If so then the time origin
+for the sorting is specified by the timewrap parameter.  This time
+should precede the first observation and follow the last observation
+in a 24 hour cycle.
+.le
+
+.ce
+-- DISPERSION  CORRECTION PARAMETERS --
+.ls linearize = yes (dispcor)
+Interpolate the spectra to a linear dispersion sampling?  If yes the
+spectra will be interpolated to a linear or log linear sampling
+If no the nonlinear dispersion function(s) from the dispersion function
+database are assigned to the input image world coordinate system
+and the spectral data are not interpolated.
+.le
+.ls log = no (dispcor)
+Use linear logarithmic wavelength coordinates?  Linear logarithmic
+wavelength coordinates have wavelength intervals which are constant
+in the logarithm of the wavelength.
+.le
+.ls flux = yes (dispcor)
+Conserve the total flux during interpolation?  If \fIno\fR the output
+spectrum is interpolated from the input spectrum at each output
+wavelength coordinate.  If \fIyes\fR the input spectrum is integrated
+over the extent of each output pixel.  This is slower than
+simple interpolation.
+.le
+
+.ce
+-- SKY SUBTRACTION PARAMETERS --
+.ls combine = "average" (scombine) (average|median)
+Option for combining sky pixels at the same dispersion coordinate after any
+rejection operation.  The options are to compute the  "average" or "median"
+of the pixels.  The median uses the average of the two central
+values when the number of pixels is even.
+.le
+.ls reject = "none" (scombine) (none|minmax|avsigclip)
+Type of rejection operation performed on the pixels which overlap at each
+dispersion coordinate.  The algorithms are discussed in the
+help for \fBscombine\fR.  The rejection choices are:
+
+.nf
+      none - No rejection
+    minmax - Reject the low and high pixels
+ avsigclip - Reject pixels using an averaged sigma clipping algorithm
+.fi
+
+.le
+.ls scale = "none" (none|mode|median|mean)
+Multiplicative scaling to be applied to each spectrum.  The choices are none
+or scale by the mode, median, or mean.  This should not be necessary if the
+flat field and throughput corrections have been properly made. 
+.le
+.ih
+ENVIRONMENT PARAMETERS
+The environment parameter \fIimtype\fR is used to determine the extension
+of the images to be processed and created.  This allows use with any
+supported image extension.  For STF images the extension has to be exact;
+for example "d1h".
+.ih
+DESCRIPTION
+The \fBdoargus\fR reduction task is specialized for scattered light
+subtraction, extraction, flat
+fielding, fiber throughput correction, wavelength calibration, and sky
+subtraction of \fIArgus\fR fiber spectra.  It is a
+command language script which collects and combines the functions and
+parameters of many general purpose tasks to provide a single, complete data
+reduction path.  The task provides a degree of guidance, automation, and
+record keeping necessary when dealing with the large amount of data
+generated by these multifiber instruments.
+
+The general organization of the task is to do the interactive setup steps
+first using representative calibration data and then perform the majority
+of the reductions automatically, and possibly as a background process, with
+reference to the setup data.  In addition, the task determines which setup
+and processing operations have been completed in previous executions of the
+task and, contingent on the \fIredo\fR and \fIupdate\fR options, skip or
+repeat some or all the steps.
+
+The description is divided into a quick usage outline followed by details
+of the parameters and algorithms.  The usage outline is provided as a
+checklist and a refresher for those familiar with this task and the
+component tasks.  It presents only the default or recommended usage for
+Argus since there are many variations possible.  Because \fBdoargus\fR
+combines many separate, general purpose tasks the description given here
+refers to these tasks and leaves some of the details to their help
+documentation.
+
+\fBUsage Outline\fR
+
+.ls 6 [1]
+The images are first processed with \fBccdproc\fR for overscan,
+bias, and dark corrections.
+The \fBdoargus\fR task will abort if the image header keyword CCDPROC,
+which is added by \fBccdproc\fR, is missing.  If the data processed outside
+of the IRAF \fBccdred\fR package then a dummy CCDPROC keyword should be
+added to the image headers; say with \fBhedit\fR.
+.le
+.ls [2]
+Set the \fBdoargus\fR parameters with \fBeparam\fR.  Specify the object
+images to be processed, the flat field image as the aperture reference and
+the flat field, and one or more arc images.  A throughput file or image,
+such as a blank sky observation, may also be specified.  If there are many
+object or arc spectra per setup you might want to prepare "@ files".
+Prepare and specify the aperture identification table if desired.  If
+the image headers contain the fiber identification information with
+SLFIB keywords then specify an image for the aperture identification table.
+You might wish to verify the geometry parameters,
+separations, dispersion direction, etc., which may change with different
+detector setups.  The processing parameters are set for complete reductions
+but for quicklook you might not use the clean option or dispersion
+calibration and sky subtraction.
+
+The parameters are set for a particular Argus configuration and different
+configurations may use different flat fields, arcs, and aperture
+identification tables.
+.le
+.ls [3]
+Run the task.  This may be repeated multiple times with different
+observations and the task will generally only do the setup steps
+once and only process new images.  Queries presented during the
+execution for various interactive operations may be answered with
+"yes", "no", "YES", or "NO".  The lower case responses apply just
+to that query while the upper case responses apply to all further
+such queries during the execution and no further queries of that
+type will be made.
+.le
+.ls [4]
+The apertures are defined using the specified aperture reference image.
+The spectra are found automatically and apertures assigned based on
+task parameters and the aperture identification table.  Unassigned
+fibers may have a negative beam number and will be ignored in subsequent
+processing.  The resize option sets the aperture size to the widths of
+the profiles at a fixed fraction of the peak height.  The interactive
+review of the apertures is recommended.  If the identifications are off
+by a shift the 'o' key is used.  To exit the aperture review type 'q'.
+.le
+.ls [5]
+The fiber positions at a series of points along the dispersion are measured
+and a function is fit to these positions.  This may be done interactively to
+adjust the fitting parameters.  Not all fibers need be examined and the "NO"
+response will quit the interactive fitting.  To exit the interactive
+fitting type 'q'.
+.le
+.ls [6]
+If scattered light subtraction is to be done the flat field image is
+used to define the scattered light fitting parameters interactively.
+If one is not specified then the aperture reference image is used for
+this purpose.
+
+There are two queries for the interactive fitting.  A graph of the
+data between the defined reference apertures separated by a specified
+buffer distance is first shown.  The function order and type may be
+adjusted.  After quiting with 'q' the user has the option of changing
+the buffer value and returning to the fitting, changing the image line
+or column to check if the fit parameters are satisfactory at other points,
+or to quit and accept the fit parameters.  After fitting all points
+across the dispersion another graph showing the scattered light from
+the individual fits is shown and the smoothing parameters along the
+dispersion may be adjusted.  Upon quiting with 'q' you have the option
+of checking other cuts parallel to the dispersion or quiting and finishing
+the scattered light function smoothing and subtraction.
+
+If there is a throughput image then this is corrected for scattered light
+noninteractively using the previous fitting parameters.
+.le
+.ls [7]
+If flat fielding is to be done the flat field spectra are extracted.  The
+average spectrum over all fibers is determined and a function is fit
+interactively (exit with 'q').  This function is generally of sufficiently
+high order that the overall shape is well fit.  This function is then used
+to normalize the individual flat field spectra.  If a throughput image, a
+sky flat, is specified then the total sky counts through each fiber are
+used to correct the total flat field counts.  Alternatively, a separately
+derived throughput file can be used for specifying throughput corrections.
+If neither type of throughput is used the flat field also provides the
+throughput correction.  The final response spectra are normalized to a unit
+mean over all fibers.  The relative average throughput for each fiber is
+recorded in the log and possibly printed to the terminal.
+.le
+.ls [8]
+If dispersion correction is selected the first arc in the arc list is
+extracted.  The middle fiber is used to identify the arc lines and define
+the dispersion function using the task \fBautoidentify\fR.  The
+\fIcrval\fR and \fIcdelt\fR parameters are used in the automatic
+identification.  Whether or not the automatic identification is
+successful you will be shown the result of the arc line identification.
+If the automatic identification is not successful identify a few arc
+lines with 'm' and use the 'l' line list identification command to
+automatically add additional lines and fit the dispersion function.  Check
+the quality of the dispersion function fit with 'f'.  When satisfied exit
+with 'q'.
+.le
+.ls [9]
+The remaining fibers are automatically reidentified.  You have the option
+to review the line identifications and dispersion function for each fiber
+and interactively add or delete arc lines and change fitting parameters.
+This can be done selectively, such as when the reported RMS increases
+significantly.
+.le
+.ls [10]
+If the spectra are to be resampled to a linear dispersion system
+(which will be the same for all spectra) default dispersion parameters
+are printed and you are allowed to adjust these as desired.
+.le
+.ls [11]
+If the sky line alignment option is selected and the sky lines have not
+been identified for a particular aperture identification table then you are
+asked to mark one or more sky lines.  You may simply accept the wavelengths
+of these lines as defined by the dispersion solution for this spectrum and
+fiber or you may specify knowns wavelengths for the lines. These lines will
+be reidentified in all object spectra extracted and a mean zeropoint shift
+will be added to the dispersion solution.  This has the effect of aligning
+these lines to optimize sky subtraction.
+.le
+.ls [12]
+The object spectra are now automatically scattered light subtracted,
+ extracted, flat fielded, and dispersion corrected.
+.le
+.ls [13]
+When sky subtracting, the individual sky spectra may be reviewed and some
+spectra eliminated using the 'd' key.  The last deleted spectrum may be
+recovered with the 'e' key.  After exiting the review with 'q' you are
+asked for the combining option.  The type of combining is dictated by the
+number of sky fibers.
+.le
+.ls [14]
+The option to examine the final spectra with \fBsplot\fR may be given.
+To exit type 'q'.
+.le
+.ls [15]
+If scattered light is subtracted from the input data a copy of the
+original image is made by appending "noscat" to the image name.
+If the data are reprocessed with the \fIredo\fR flag the original
+image will be used again to allow modification of the scattered
+light parameters.
+
+The final spectra will have the same name as the original 2D images
+with a ".ms" extension added.  The flat field and arc spectra may
+also have part of the aperture identification table name added, if
+used, to
+allow different configurations to use the same 2D flat field and arcs
+but with different aperture definitions.  If using the sky alignment
+option an image "align" with the aperture identification table name
+applied will also be created.
+.le
+
+\fBSpectra and Data Files\fR
+
+The basic input consists of Argus object and
+calibration spectra stored as IRAF images.
+The type of image format is defined by the
+environment parameter \fIimtype\fR.  Only images with that extension will
+be processed and created.
+The raw CCD images must
+be processed to remove overscan, bias, and dark count effects.
+This is generally done using the \fBccdred\fR package.
+The \fBdoargus\fR task will abort if the image header keyword CCDPROC,
+which is added by \fBccdproc\fR, is missing.  If the data processed outside
+of the IRAF \fBccdred\fR package then a dummy CCDPROC keyword should be
+added to the image headers; say with \fBhedit\fR.
+Flat fielding is
+generally not done at this stage but as part of \fBdoargus\fR.
+If flat fielding is done as part of the basic CCD processing then
+a flattened flat field, blank sky observation, or throughput file
+should still be created for applying fiber throughput corrections.
+
+The task \fBdoargus\fR uses several types of calibration spectra.  These
+are flat fields, blank sky flat fields, comparison lamp spectra, and auxiliary
+mercury line (from the dome lights) or sky line spectra.  The flat field,
+throughput image or file, and auxiliary emission line spectra are optional.
+If a flat field is used then the sky flat
+or throughput file is optional assuming the flat field has the same fiber
+iillumination.  It is legal to specify only a throughput image or file and
+leave the flat field blank in order to simply apply a throughput
+correction.  Because only the total counts through each fiber are used from
+a throughput image, sky flat exposures need not be of high signal per
+pixel.
+
+There are two types of dispersion calibration methods.  One is to take arc
+calibration exposures through all fibers periodically and apply the
+dispersion function derived from one or interpolated between pairs to the
+object fibers.  This is the usual method with Argus.
+A second (uncommon) method is to use \fIauxiliary
+line spectra\fR such as lines in the dome lights or sky lines to monitor
+shifts relative to a few actual arc exposures.  The main reason to do this
+is if taking arc exposures through all fibers is inconvenient.
+
+The assignment of arc or auxiliary line calibration exposures to object
+exposures is generally done by selecting the nearest in time and
+interpolating.  There are other options possible which are described under
+the task \fBrefspectra\fR.  The most general option is to define a table
+giving the object image name and the one or two arc spectra to be assigned
+to that object.  That file is called an \fIarc assignment table\fR and it
+is one of the optional setup files which can used with \fBdoargus\fR.
+
+The first step in the processing is identifying the spectra in the images.
+The default method is to use the fact that object and sky fibers alternate
+and assign sequential numbers to the fibers so that the sky fibers are the
+even aperture numbers and the object fibers are the odd aperture numbers.
+In this case the beam numbers are not used (and are the same as the
+aperture numbers) and there are no object identifications associated with the
+spectra.
+
+A very useful, optional, setup parameter is an \fIaperture identification
+table\fR.  The table contains information about the fiber assignments
+including object titles.  The table is either a text file or an image
+containing the keywords SLFIB.  An aperture identification file contains
+lines consisting of an aperture number, a beam number, and an object
+identification.  In an image the SLFIB keywords contain the aperture
+number, the beam numbers, optional right ascension and declination, and a
+title.  The aperture identification information must be in the same order
+as the fibers in the image.  The aperture number may be any unique number
+but it is recommended that the normal sequential fiber numbers be used.
+The beam number may be used to flag object or sky spectra or simply be the
+same as the aperture number.  The object identifications are optional but
+it is good practice to include them so that the data will contain the
+object information independent of other records.  Figure 1 shows an example
+of a file for a configuration called LMC123.
+
+.nf
+
+    Figure 1: Example Aperture Identification File
+
+    cl> type LMC124
+    1 1 143
+    2 0 sky
+    3 1 121
+       .
+       .
+       .
+    47 1 s92
+    48 0 sky
+
+.fi
+Note the identification of the sky fibers with beam number 0 and the
+object fibers with 1.  Any broken fibers should be included and
+identified by a different beam number, say beam number -1, to give the
+automatic spectrum finding operation the best chance to make the
+correct identifications.  Naturally the identification table will vary
+for each configuration.
+Additional information about the aperture identification
+table may be found in the description of the task \fBapfind\fR.
+
+In more recent Argus data the fiber information is included in the
+image header under the keywords SLFIB.  In this case you don't need
+to prepare a file and simply specify the name of an image, typically
+the same as the aperture reference image, for the aperture identification
+table.
+
+The final reduced spectra are recorded in two or three dimensional IRAF
+images.  The images have the same name as the original images with an added
+".ms" extension.  Each line in the reduced image is a one dimensional
+spectrum with associated aperture, wavelength, and identification
+information.  When the \fIextras\fR parameter is set the lines in the
+third dimension contain additional information (see
+\fBapsum\fR for further details).  These spectral formats are accepted by the
+one dimensional spectroscopy tools such as the plotting tasks \fBsplot\fR
+and \fBspecplot\fR.  The special task \fBscopy\fR may be used to extract
+specific apertures or to change format to individual one dimensional
+images.
+
+\fBPackage Parameters\fR
+
+The \fBargus\fR package parameters set parameters affecting all the
+tasks in the package.
+The dispersion axis parameter defines the image axis along which the
+dispersion runs.  This is used if the image header doesn't define the
+dispersion axis with the DISPAXIS keyword.
+The observatory parameter is only required
+for data taken with fiber instruments other than Argus.
+The spectrum interpolation type might be changed to "sinc" but
+with the cautions given in \fBonedspec.package\fR.
+The other parameters define the standard I/O functions.
+The verbose parameter selects whether to print everything which goes
+into the log file on the terminal.  It is useful for monitoring
+what the \fBdoargus\fR task does.  The log and plot files are useful for
+keeping a record of the processing.  A log file is highly recommended.
+A plot file provides a record of apertures, traces, and extracted spectra
+but can become quite large.
+The plotfile is most conveniently viewed and printed with \fBgkimosaic\fR.
+
+\fBProcessing Parameters\fR
+
+The list of objects and arcs can be @ files if desired.  The aperture
+reference spectrum is usually the same as the flat field spectrum though it
+could be any exposure with enough signal to accurately define the positions
+and trace the spectra.  The first list of arcs are the standard Th-Ar or
+HeNeAr comparison arc spectra (they must all be of the same type).  The
+second list of arcs are the auxiliary emission line exposures mentioned
+previously.
+
+The detector read out noise and gain are used for cleaning and variance
+(optimal) extraction.
+The dispersion axis defines the wavelength direction of spectra in
+the image if not defined in the image header by the keyword DISPAXIS.  The
+width and separation parameters define the dimensions (in pixels) of the
+spectra (fiber profile) across the dispersion.  The width parameter
+primarily affects the centering.  The maximum separation parameter is
+important if missing spectra are to
+be correctly skipped.  The number of fibers can be left at the default
+and the task will try to account for unassigned or missing fibers.
+However, this may lead to occasional incorrect
+identifications so it is recommended that only the true number of
+fibers be specified.  The aperture identification table was described
+earlier.
+
+The approximate central wavelength and dispersion are used for the
+automatic identification of the arc reference.  They may be specified
+as image header keywords or values.  The INDEF values search the
+entire range of the coordinate reference file but the automatic
+line identification algorithm works much better and faster if
+approximate values are given.
+
+The task needs to know which fibers are object and which are sky
+if sky subtraction is to be done.  One could explicitly
+give the aperture numbers but the recommended way is to use the default
+of selecting every second fiber as sky.  If no list of aperture or beam
+numbers is given
+then all apertures or beam numbers are selected.  Sky subtracted sky
+spectra are useful for evaluating the sky subtraction.  Since only
+the spectra identified as objects are sky subtracted one can exclude
+fibers from the sky subtraction.  For example, to eliminate the sky
+spectra from the final results the \fIobjaps\fR parameter could be
+set to "1x2".  All other fibers will remain in the extracted spectra
+but will not be sky subtracted.
+
+The next set of parameters select the processing steps and options.  The
+scattered light option allows fitting and subtracting a scattered light
+surface from the input object and flat field.  If there is significant
+scattered light which is not subtracted the fiber throughput correction
+will not be accurate.  The
+flat fitting option allows fitting and removing the overall shape of the
+flat field spectra while preserving the pixel-to-pixel response
+corrections.  This is useful for maintaining the approximate object count
+levels and not introducing the reciprocal of the flat field spectrum into
+the object spectra.  The \fIclean\fR option invokes a profile fitting and
+deviant point rejection algorithm as well as a variance weighting of points
+in the aperture.  These options require knowing the effective (i.e.
+accounting for any image combining) read out noise and gain.  For a
+discussion of cleaning and variance weighted extraction see
+\fBapvariance\fR and \fBapprofiles\fR.
+
+The dispersion correction option selects whether to extract arc spectra,
+determine a dispersion function, assign them to the object spectra, and,
+possibly, resample the spectra to a linear (or log-linear) wavelength
+scale.  If simultaneous arc fibers are defined there is an option to delete
+them from the final spectra when they are no longer needed.
+
+The sky alignment option allows applying a zeropoint dispersion shift
+to all fibers based on one or more sky lines.  This requires all fibers
+to have the sky lines visible.  When there are sky lines this will
+improve the sky subtraction if there is a systematic error in the
+fiber iillumination between the sky and the arc calibration.
+
+The sky subtraction option selects whether to combine the sky fiber spectra
+and subtract this sky from the object fiber spectra.  It is also possible
+to subtract the sky and object fibers by pairs.  \fIDispersion
+correction and sky subtraction are independent operations.\fR  This means
+that if dispersion correction is not done then the sky subtraction will be
+done with respect to pixel coordinates.  This might be desirable in some
+quick look cases though it is incorrect for final reductions.
+
+The sky subtraction option has two additional options.  The individual sky
+spectra may be examined and contaminated spectra deleted interactively
+before combining.  This can be a useful feature in crowded regions.  The
+final combined sky spectrum (or individual skys if subtracting by
+pairs) may be saved for later inspection in an image
+with the spectrum name prefixed by \fBsky\fR.
+
+After a spectrum has been processed it is possible to examine the results
+interactively using the \fBsplot\fR tasks.  This option has a query which
+may be turned off with "YES" or "NO" if there are multiple spectra to be
+processed.
+
+Generally once a spectrum has been processed it will not be reprocessed if
+specified as an input spectrum.  However, changes to the underlying
+calibration data can cause such spectra to be reprocessed if the
+\fIupdate\fR flag is set.  The changes which will cause an update are a new
+aperture identification table, a new reference image, new flat fields, and a
+new arc reference.  If all input spectra are to be processed regardless of
+previous processing the \fIredo\fR flag may be used.  Note that
+reprocessing clobbers the previously processed output spectra.
+
+The \fIbatch\fR processing option allows object spectra to be processed as
+a background or batch job.  This will only occur if sky spectra editing and
+\fBsplot\fR review (interactive operations) are turned off, either when the
+task is run or by responding with "NO" to the queries during processing.
+
+The \fIlistonly\fR option prints a summary of the processing steps which
+will be performed on the input spectra without actually doing anything.
+This is useful for verifying which spectra will be affected if the input
+list contains previously processed spectra.  The listing does not include
+any arc spectra which may be extracted to dispersion calibrate an object
+spectrum.
+
+The last parameter (excluding the task mode parameter) points to another
+parameter set for the algorithm parameters.  The way \fBdoargus\fR works
+this may not have any value and the parameter set \fBparams\fR is always
+used.  The algorithm parameters are discussed further in the next section.
+
+\fBAlgorithms and Algorithm Parameters\fR
+
+This section summarizes the various algorithms used by the \fBdoargus\fR
+task and the parameters which control and modify the algorithms.  The
+algorithm parameters available to the user are collected in the parameter
+set \fBparams\fR.  These parameters are taken from the various general
+purpose tasks used by the \fBdoargus\fR processing task.  Additional
+information about these parameters and algorithms may be found in the help
+for the actual task executed.  These tasks are identified in the parameter
+section listing in parenthesis.  The aim of this parameter set organization
+is to collect all the algorithm parameters in one place separate from the
+processing parameters and include only those which are relevant for
+Argus.  The parameter values can be changed from the
+defaults by using the parameter editor,
+.nf
+
+	cl> epar params
+
+.fi
+or simple typing \fIparams\fR.  The parameter editor can also be
+entered when editing the \fBdoargus\fR parameters by typing \fI:e
+params\fR or simply \fI:e\fR if positioned at the \fIparams\fR
+parameter.
+
+\fBExtraction\fR
+
+The identification of the spectra in the two dimensional images and their
+scattered light subtraction and extraction to one dimensional spectra
+in multispec format is accomplished
+using the tasks from the \fBapextract\fR package.  The first parameters
+through \fInsubaps\fR control the extractions.
+
+The dispersion line is that used for finding the spectra, for plotting in
+the aperture editor, and as the starting point for tracing.  The default
+value of \fBINDEF\fR selects the middle of the image.  The aperture
+finding, adjusting, editing, and tracing operations also allow summing a
+number of dispersion lines to improve the signal.  The number of lines is
+set by the \fInsum\fR parameter.
+
+The order parameter defines whether the order of the aperture
+identifications in the aperture identification table (or the default
+sequential numbers if no table is used) is in the same sense as the image
+coordinates (increasing) or the opposite sense (decreasing).  If the
+aperture identifications turn out to be opposite to what is desired when
+viewed in the aperture editing graph then simply change this parameter.
+
+The basic data output by the spectral extraction routines are the one
+dimensional spectra.  Additional information may be output when the
+\fIextras\fR option is selected and the cleaning or variance weighting
+options are also selected.  In this case a three dimensional image is
+produced with the first element of the third dimension being the cleaned
+and/or weighted spectra, the second element being the uncleaned and
+unweighted spectra, and the third element being an estimate of the sigma
+of each pixel in the extracted spectrum.  Currently the sigma data is not
+used by any other tasks and is only for reference.
+
+The initial step of finding the fiber spectra in the aperture reference
+image consists of identifying the peaks in a cut across the dispersion,
+eliminating those which are closer to each other than the \fIminsep\fR
+distance, and then keeping the specified \fInfibers\fR highest peaks.  The
+centers of the profiles are determined using the \fBcenter1d\fR algorithm
+which uses the \fIwidth\fR parameter.
+
+Apertures are then assigned to each spectrum.  The initial edges of the
+aperture relative to the center are defined by the \fIlower\fR and
+\fIupper\fR parameters.
+The initial apertures are the same for all spectra but they can each be
+automatically resized.  The automatic resizing sets the aperture limits
+at a fraction of the peak relative to the interfiber minimum.
+The default \fIylevel\fR is to resize the apertures to 5% of the peak.
+See the description for the task \fBapresize\fR for further details.
+
+The user is given the opportunity to graphically review and adjust the
+aperture definitions.  This is recommended
+and it is fundamentally important that the correct aperture/beam numbers
+be associated with the proper fibers;
+otherwise the spectrum
+identifications will not be for the objects they say.  An important command in
+this regard is the 'o' key which allows reordering the identifications.
+This is required if the first
+fiber is actually missing since the initial assignment begins with the
+first spectrum found.  The
+aperture editor is a very powerful tool and is described in detail as
+\fBapedit\fR.
+
+The next set of parameters control the tracing and function fitting of the
+aperture reference positions along the dispersion direction.  The position
+of a spectrum across the dispersion is determined by the centering
+algorithm (see \fBcenter1d\fR) at a series of evenly spaced steps, given by
+the parameter \fIt_step\fR, along the dispersion.  The step size should be
+fine enough to follow position changes but it is not necessary to measure
+every point.  The fitted points may jump around a little bit due to noise
+and cosmic rays even when summing a number of lines.  Thus, a smooth
+function is fit.  The function type, order, and iterative rejection of
+deviant points is controlled by the other trace parameters.  For more
+discussion consult the help pages for \fBaptrace\fR and \fBicfit\fR.  The
+default is to fit a cubic spline of three pieces with a single iteration of
+3 sigma rejection.
+
+The actual extraction of the spectra by summing across the aperture at each
+point along the dispersion is controlled by the next set of parameters.
+The default extraction simply sums the pixels using partial pixels at the
+ends.  The options allow selection of a weighted sum based on a Poisson
+variance model using the \fIreadnoise\fR and \fIgain\fR detector
+parameters.  Note that if the \fIclean\fR option is selected the variance
+weighted extraction is used regardless of the \fIweights\fR parameter.  The
+sigma thresholds for cleaning are also set in the \fBparams\fR parameters.
+For more on the variance weighted extraction and cleaning see
+\fBapvariance\fR and \fBapprofiles\fR as well as \fBapsum\fR.
+
+The last parameter, \fInsubaps\fR, is used only in special cases when it is
+desired to subdivide the fiber profiles into subapertures prior to
+dispersion correction.  After dispersion correction the subapertures are
+then added together.  The purpose of this is to correct for wavelength
+shifts across a fiber.
+
+\fBScattered Light Subtraction\fR
+
+Scattered light may be subtracted from the input two dimensional image as
+the first step.  This is done using the algorithm described in
+\fBapscatter\fR.  This can be important if there is significant scattered
+light since the flat field/throughput correction will otherwise be
+incorrect.  The algorithm consists of fitting a function to the data
+outside the defined apertures by a specified \fIbuffer\fR at each line or
+column across the dispersion.  The function fitting parameters are the same
+at each line.  Because the fitted functions are independent at each line or
+column a second set of one dimensional functions are fit parallel to the
+dispersion using the evaluated fit values from the cross-dispersion step.
+This produces a smooth scattered light surface which is finally subtracted
+from the input image.  Again the function fitting parameters are the
+same at each line or column though they may be different than the parameters
+used to fit across the dispersion.
+
+The first time the task is run with a particular flat field (or aperture
+reference image if no flat field is used) the scattered light fitting
+parameters are set interactively using that image.  The interactive step
+selects a particular line or column upon which the fitting is done
+interactively with the \fBicfit\fR commands.  A query is first issued
+which allows skipping this interactive stage.  Note that the interactive
+fitting is only for defining the fitting functions and orders.  When
+the graphical \fBicfit\fR fitting is exited (with 'q') there is a second prompt
+allowing you to change the buffer distance (in the first cross-dispersion
+stage) from the apertures, change the line/column, or finally quit.
+
+The initial fitting parameters and the final set parameters are recorded
+in the \fBapscat1\fR and \fBapscat2\fR hidden parameter sets.  These
+parameters are then used automatically for every subsequent image
+which is scattered light corrected.
+
+The scattered light subtraction modifies the input 2D images.  To preserve
+the original data a copy of the original image is made with the same
+root name and the word "noscat" appended.  The scattered light subtracted
+images will have the header keyword "APSCATTE" which is how the task
+avoids repeating the scattered light subtraction during any reprocessing.
+However if the \fIredo\fR option is selected the scattered light subtraction
+will also be redone by first restoring the "noscat" images to the original
+input names.
+
+\fBFlat Field and Fiber Throughput Corrections\fR
+
+Flat field corrections may be made during the basic CCD processing; i.e.
+direct division by the two dimensional flat field observation.  In that
+case do not specify a flat field spectrum; use the null string "".  The
+\fBdoargus\fR task provides an alternative flat field response correction
+based on division of the extracted object spectra by the extracted flat field
+spectra.  A discussion of the theory and merits of flat fielding directly
+verses using the extracted spectra will not be made here.  The
+\fBdoargus\fR flat fielding algorithm is the \fIrecommended\fR method for
+flat fielding since it works well and is not subject to the many problems
+involved in two dimensional flat fielding.
+
+In addition to correcting for pixel-to-pixel response the flat field step
+also corrects for differences in the fiber throughput.  Thus, even if the
+pixel-to-pixel flat field corrections have been made in some other way it
+is desirable to use a sky or dome flat observation for determining a fiber
+throughput correction.  Alternatively, a separately derived throughput
+file may be specified.  This file consists of the aperture numbers
+(the same as used for the aperture reference) and relative throughput
+numbers.
+
+The first step is extraction of the flat field spectrum, if specified,
+using the reference apertures.  Only one flat field is allowed so if
+multiple flat fields are required the data must be reduced in groups.
+After extraction one or more corrections are applied.  If the \fIfitflat\fR
+option is selected (the default) the extracted flat field spectra are
+averaged together and a smooth function is fit.  The default fitting
+function and order are given by the parameters \fIf_function\fR and
+\fIf_order\fR.  If the parameter \fIf_interactive\fR is "yes" then the
+fitting is done interactively using the \fBfit1d\fR task which uses the
+\fBicfit\fR interactive fitting commands.
+
+The fitted function is divided into the individual flat field spectra to
+remove the basic shape of the spectrum while maintaining the relative
+individual pixel responses and any fiber to fiber differences.  This step
+avoids introducing the flat field spectrum shape into the object spectra
+and closely preserves the object counts.
+
+If a throughput image is available (an observation of blank sky
+usually at twilight) it is extracted.  If no flat field is used the average
+signal through each fiber is computed and this becomes the response
+normalization function.  Note that a dome flat may be used in place of a
+sky in the sky flat field parameter for producing throughput only
+corrections.  If a flat field is specified then each sky spectrum is
+divided by the appropriate flat field spectrum.  The total counts through
+each fiber are multiplied into the flat field spectrum thus making the sky
+throughput of each fiber the same.  This correction is important if the
+iillumination of the fibers differs between the flat field source and the
+sky.  Since only the total counts are required the sky or dome flat field
+spectra need not be particularly strong though care must be taken to avoid
+objects.
+
+Instead of a sky flat or other throughput image a separately derived
+throughput file may be used.  It may be used with or without a
+flat field.
+
+The final step is to normalize the flat field spectra by the mean counts of
+all the fibers.  This normalization step is simply to preserve the average
+counts of the extracted object and arc spectra after division by the
+response spectra.  The final relative throughput values are recorded in the
+log and possibly printed on the terminal.
+
+These flat field response steps and algorithm are available as a separate
+task called \fBmsresp1d\fR.
+
+\fBDispersion Correction\fR
+
+Dispersion corrections are applied to the extracted spectra if the
+\fBdispcor\fR parameter is set.  This can be a complicated process which
+the \fBdoargus\fR task tries to simplify for you.  There are three basic
+steps involved; determining the dispersion functions relating pixel
+position to wavelength, assigning the appropriate dispersion function to a
+particular observation, and resampling the spectra to evenly spaced pixels
+in wavelength.
+
+The comparison arc spectra are used to define dispersion functions for the
+fibers using the tasks \fBautoidentify\fR and \fBreidentify\fR.  The
+interactive \fBautoidentify\fR task is only used on the central fiber of the
+first arc spectrum to define the basic reference dispersion solution from
+which all other fibers and arc spectra are automatically derived using
+\fBreidentify\fR. \fBAutoidentify\fR attempts to automatically identify
+the arc lines using the \fIcrval\fR and \fIcdelt\fR parameters.  Whether
+or not it is successful the user is presented with the interactive
+identification graph.  The automatic identifications can be reviewed and a
+new solution or corrections to the automatic solution may be performed.
+
+The set of arc dispersion function parameters are from \fBautoidentify\fR and
+\fBreidentify\fR.  The parameters define a line list for use in
+automatically assigning wavelengths to arc lines, a parameter controlling
+the width of the centering window (which should match the base line
+widths), the dispersion function type and order, parameters to exclude bad
+lines from function fits, and parameters defining whether to refit the
+dispersion function, as opposed to simply determining a zero point shift,
+and the addition of new lines from the line list when reidentifying
+additional arc spectra.  The defaults should generally be adequate and the
+dispersion function fitting parameters may be altered interactively.  One
+should consult the help for the two tasks for additional details of these
+parameters and the operation of \fBautoidentify\fR.
+
+Generally, taking a number of comparison arc lamp exposures interspersed
+with the program spectra is sufficient to accurately dispersion calibrate
+Argus spectra.  Dispersion functions are
+determined independently for each fiber of each arc image and then assigned
+to the matching fibers in the program object observations.  The assignment
+consists of selecting one or two arc images to calibrate each object
+image.
+
+However, there is another calibration option which may be of interest.
+This option uses auxiliary line spectra, such as from dome lights or night
+sky lines, to monitor wavelength zero point shifts which are added to the
+basic dispersion function derived from a single reference arc.  Initially
+one of the auxiliary fiber spectra is plotted interactively by
+\fBidentify\fR with the reference dispersion function for the appropriate
+fiber.  The user marks one or more lines which will be used to compute zero
+point wavelength shifts in the dispersion functions automatically.  In this
+case it is auxiliary arc images which are assigned to particular objects.
+
+The arc or auxiliary line image assignments may be done either explicitly with an arc assignment
+table (parameter \fIarctable\fR) or based on a header parameter.  The task
+used is \fBrefspectra\fR and the user should consult this task if the
+default behavior is not what is desired.  The default is to interpolate
+linearly between the nearest arcs based on the Julian date (corrected to
+the middle of the exposure).  The Julian date and a local Julian day number
+(the day number at local noon) are computed automatically by the task
+\fBsetjd\fR and recorded in the image headers under the keywords JD and
+LJD.  In addition the universal time at the middle of the exposure, keyword
+UTMIDDLE, is computed by the task \fBsetairmass\fR and this may also be used
+for ordering the arc and object observations.
+
+An optional step is to use sky lines in the spectra to compute a zeropoint
+dispersion shift that will align the sky lines.  This may improve sky
+subtraction if the iillumination is not the same between the arc calibration
+and the sky.  When selected the object spectrum is dispersion corrected
+using a non-linear dispersion function to avoid resampling the spectrum.
+The sky lines are then reidentified in wavelength space from a template
+list of sky lines.  The mean shift in the lines for each fiber relative to
+the template in that fiber is computed to give the zeropoint shift.  The
+database file is created when the first object is extracted.  You are asked
+to mark the sky lines in one fiber and then the lines are automatically
+reidentified in all other fibers.  Note that this technique requires the
+sky lines be found in all fibers.
+
+The last step of dispersion correction (resampling the spectrum to evenly
+spaced pixels in wavelength) is optional and relatively straightforward.
+If the \fIlinearize\fR parameter is no then the spectra are not resampled
+and the nonlinear dispersion information is recorded in the image header.
+Other IRAF tasks (the coordinate description is specific to IRAF) will use
+this information whenever wavelengths are needed.  If linearizing is
+selected a linear dispersion relation, either linear in the wavelength or
+the log of the wavelength, is defined once and applied to every extracted
+spectrum.  The resampling algorithm  parameters allow selecting the
+interpolation function type, whether to conserve flux per pixel by
+integrating across the extent of the final pixel, and whether to linearize
+to equal linear or logarithmic intervals.  The latter may be appropriate
+for radial velocity studies.  The default is to use a fifth order
+polynomial for interpolation, to conserve flux, and to not use logarithmic
+wavelength bins.  These parameters are described fully in the help for the
+task \fBdispcor\fR which performs the correction.  The interpolation
+function options and the nonlinear dispersion coordinate system is
+described in the help topic \fBonedspec.package\fR.
+
+\fBSky Subtraction\fR
+
+Sky subtraction is selected with the \fIskysubtract\fR processing option.
+The sky spectra are selected by their aperture and beam numbers.
+If the \fIskyedit\fR
+option is selected the sky spectra are plotted using the task
+\fBspecplot\fR.  By default they are superposed to allow identifying
+spectra with unusually high signal due to object contamination.  To
+eliminate a sky spectrum from consideration point at it with the cursor and
+type 'd'.  The last deleted spectrum may be undeleted with 'e'.  This
+allows recovery of incorrect or accidental deletions.
+
+If the combining option is "none" then the sky and object fibers are
+paired and one sky is subtracted from one object and the saved sky will
+be the individual sky fiber spectra.
+
+However, the usual
+case is to combine the individual skys into a single master sky spectrum
+which is then subtracted from each object spectrum.
+The sky combining algorithm parameters define how the individual sky fiber
+spectra, after interactive editing, are combined before subtraction from
+the object fibers.  The goals of combining are to reduce noise, eliminate
+cosmic-rays, and eliminate fibers with inadvertent objects.  The common
+methods for doing this to use a median and/or a special sigma clipping
+algorithm (see \fBscombine\fR for details).  The scale
+parameter determines whether the individual skys are first scaled to a
+common mode.  The scaling should be used if the throughput is uncertain,
+but in that case you probably did the wrong thing in the throughput
+correction.  If the sky subtraction is done interactively, i.e. with the
+\fIskyedit\fR option selected, then after selecting the spectra to be
+combined a query is made for the combining algorithm.  This allows
+modifying the default algorithm based on the number of sky spectra
+selected since the "avsigclip" rejection algorithm requires at least
+three spectra.
+
+The combined sky spectrum is subtracted from only those spectra specified
+by the object aperture and beam numbers.  Other spectra
+are retained unchanged.  One may include the sky spectra as
+object spectra to produce residual sky spectra for analysis.  The combined
+master sky spectra may be saved if the \fIsaveskys\fR parameter is set.
+The saved sky is given the name of the object spectrum with the prefix
+"sky".
+.ih
+EXAMPLES
+1.  The following example uses artificial data and may be executed
+at the terminal (with IRAF V2.10).  This is also the sequence performed
+by the test procedure "demos qtest".
+
+.nf
+ar> demos mkqdata
+Creating image demoobj ...
+Creating image demoflat ...
+Creating image demoarc ...
+hy> argus.verbose = yes
+hy> doargus demoobj apref=demoflat flat=demoflat arcs1=demoarc \
+>>> fib=13 width=4. minsep=5. maxsep=7. clean- splot+
+Set reference apertures for demoflat
+Resize apertures for demoflat?  (yes):
+Edit apertures for demoflat?  (yes):
+<Exit with 'q'>
+Fit curve to aperture 1 of demoflat interactively  (yes):
+<Exit with 'q'>
+Fit curve to aperture 2 of demoflat interactively  (yes): N
+Create response function demoflatnorm.ms
+Extract flat field demoflat
+Fit and ratio flat field demoflat
+<Exit with 'q'>
+Extract flat field demoflat
+Fit and ratio flat field demoflat
+Create the normalized response demoflatnorm.ms
+demoflatnorm.ms -> demoflatnorm.ms  using bzero: 0.
+    and bscale: 1.000001
+    mean: 1.000001  median: 1.110622  mode: 1.331709
+    upper: INDEF  lower: INDEF
+Average aperture response:
+1.  1.136281
+2.  1.208727
+3.  0.4720535
+4.  1.308195
+5.  1.344551
+6.  1.330406
+7.  0.7136359
+8.  1.218975
+9.  0.7845755
+10.  0.9705642
+11.  1.02654
+12.  0.3745525
+13.  1.110934
+Extract arc reference image demoarc
+Determine dispersion solution for demoarc
+<A dispersion solution is found automatically.>
+<Type 'f' to look at fit.  Type 'q' to exit fit.>
+<Exit with 'q'>
+
+REIDENTIFY: NOAO/IRAF V2.10BETA valdes@puppis Tue 16:01:07 11-Feb-92
+  Reference image = d....ms.imh, New image = d....ms, Refit = yes
+     Image Data Found    Fit Pix Shift User Shift  Z Shift     RMS
+d....ms - Ap 7  29/29  29/29   9.53E-4    0.00409  2.07E-7   0.273
+Fit dispersion function interactively? (no|yes|NO|YES) (yes): n
+d....ms - Ap 5  29/29  29/29   -0.0125    -0.0784  -1.2E-5   0.315
+Fit dispersion function interactively? (no|yes|NO|YES) (no): y
+d....ms - Ap 5  29/29  29/29   -0.0125    -0.0784  -1.2E-5   0.315
+d....ms - Ap 4  29/29  29/29   -0.0016    -0.0118  -2.7E-6   0.284
+Fit dispersion function interactively? (no|yes|NO|YES) (yes): N
+d....ms - Ap 4  29/29  29/29   -0.0016    -0.0118  -2.7E-6   0.284
+d....ms - Ap 3  29/29  29/29  -0.00112   -0.00865  -1.8E-6   0.282
+d....ms - Ap 2  29/29  29/29  -0.00429    -0.0282  -4.9E-6   0.288
+d....ms - Ap 1  29/29  28/29   0.00174    0.00883  6.63E-7   0.228
+d....ms - Ap 9  29/29  29/29  -0.00601    -0.0387  -6.5E-6   0.268
+d....ms - Ap 10 29/29  29/29  -9.26E-4   -0.00751  -1.7E-6   0.297
+d....ms - Ap 11 29/29  29/29   0.00215     0.0114  1.05E-6   0.263
+d....ms - Ap 12 29/29  29/29  -0.00222    -0.0154  -2.8E-6   0.293
+d....ms - Ap 13 29/29  29/29   -0.0138    -0.0865  -1.4E-5    0.29
+d....ms - Ap 14 29/29  29/29  -0.00584    -0.0378  -6.8E-6   0.281
+
+Dispersion correct demoarc
+demoarc.ms: w1 = 5785.8..., w2 = 7351.6..., dw = 6.14..., nw = 256
+  Change wavelength coordinate assignments? (yes|no|NO): n
+Extract object spectrum demoobj
+Assign arc spectra for demoobj
+[demoobj] refspec1='demoarc'
+Dispersion correct demoobj
+demoobj.ms.imh: w1 = 5785.833, w2 =  7351.63, dw = 6.140378, nw = 256
+Sky subtract demoobj:  skybeams=0
+Edit the sky spectra? (yes):
+<Exit with 'q'>
+Sky rejection option (none|minmax|avsigclip) (avsigclip):
+demoobj.ms.imh:
+Splot spectrum? (no|yes|NO|YES) (yes):
+Image line/aperture to plot (1:) (1):
+<Look at spectra and change apertures with # key>
+<Exit with 'q'>
+.fi
+.ih
+REVISIONS
+.ls DOARGUS V2.11
+A sky alignment option was added.
+
+The aperture identification can now be taken from image header keywords.
+
+The initial arc line identifications is done with the automatic line
+identification algorithm.
+.le
+.ls DOARGUS V2.10.3
+The usual output WCS format is "equispec".  The image format type to be
+processed is selected with the \fIimtype\fR environment parameter.  The
+dispersion axis parameter is now a package parameter.  Images will only
+be processed if the have the CCDPROC keyword.  A \fIdatamax\fR parameter
+has been added to help improve cosmic ray rejection.  A scattered
+light subtraction processing option has been added.
+.le
+.ih
+SEE ALSO
+apedit, apfind, approfiles, aprecenter, apresize, apsum, aptrace, apvariance,
+ccdred, center1d, dispcor, fit1d, icfit, identify, msresp1d, observatory,
+onedspec.package, refspectra, reidentify, scombine, setairmass, setjd,
+specplot, splot
+.endhelp
diff --git a/noao/imred/argus/doc/doargus.ms b/noao/imred/argus/doc/doargus.ms
new file mode 100644
index 00000000..f68883c1
--- /dev/null
+++ b/noao/imred/argus/doc/doargus.ms
@@ -0,0 +1,1725 @@
+.nr PS 9
+.nr VS 11
+.de V1
+.ft CW
+.nf
+..
+.de V2
+.fi
+.ft R
+..
+.de LS
+.br
+.in +2
+..
+.de LE
+.br
+.sp .5v
+.in -2
+..
+.ND July 1995
+.TL
+Guide to the ARGUS Reduction Task DOARGUS
+.AU
+Francisco Valdes
+.AI
+IRAF Group - Central Computer Services
+.K2
+.DY
+
+.AB
+The \fBdoargus\fR reduction task is specialized for scattered light
+subtraction, extraction, flat
+fielding, fiber throughput correction, wavelength calibration, and sky
+subtraction of \fIArgus\fR fiber spectra.  It is a
+command language script which collects and combines the functions and
+parameters of many general purpose tasks to provide a single complete data
+reduction path.  The task provides a degree of guidance, automation, and
+record keeping necessary when dealing with the large amount of data
+generated by this multifiber instrument.  This guide describes what
+this task does, it's usage, and parameters.
+.AE
+.NH
+Introduction
+.LP
+The \fBdoargus\fR reduction task is specialized for scattered light
+subtraction, extraction, flat
+fielding, fiber throughput correction, wavelength calibration, and sky
+subtraction of \fIArgus\fR fiber spectra.  It is a
+command language script which collects and combines the functions and
+parameters of many general purpose tasks to provide a single, complete data
+reduction path.  The task provides a degree of guidance, automation, and
+record keeping necessary when dealing with the large amount of data
+generated by these multifiber instruments.
+.LP
+The general organization of the task is to do the interactive setup steps
+first using representative calibration data and then perform the majority
+of the reductions automatically, and possibly as a background process, with
+reference to the setup data.  In addition, the task determines which setup
+and processing operations have been completed in previous executions of the
+task and, contingent on the \f(CWredo\fR and \f(CWupdate\fR options, skip or
+repeat some or all the steps.
+.LP
+The description is divided into a quick usage outline followed by details
+of the parameters and algorithms.  The usage outline is provided as a
+checklist and a refresher for those familiar with this task and the
+component tasks.  It presents only the default or recommended usage for
+Argus since there are many variations possible.  Because \fBdoargus\fR
+combines many separate, general purpose tasks, the description given here
+refers to these tasks and leaves some of the details to their help
+documentation.
+.NH
+Usage Outline
+.LP
+.IP [1] 6
+The images are first processed with \fBccdproc\fR for overscan,
+bias, and dark corrections.
+The \fBdoargus\fR task will abort if the image header keyword CCDPROC,
+which is added by \fBccdproc\fR, is missing.  If the data processed outside
+of the IRAF \fBccdred\fR package then a dummy CCDPROC keyword should be
+added to the image headers; say with \fBhedit\fR.
+.IP [2]
+Set the \fBdoargus\fR parameters with \fBeparam\fR.  Specify the object
+images to be processed, the flat field image as the aperture reference and
+the flat field, and one or more arc images.  A throughput file or image,
+such as a blank sky observation, may also be specified.  If there are many
+object or arc spectra per setup you might want to prepare "@ files".
+Prepare and specify an aperture identification table if desired.
+You might wish to verify the geometry parameters,
+separations, dispersion direction, etc., which may change with different
+detector setups.  The processing parameters are set for complete reductions
+but for quicklook you might not use the clean option or dispersion
+calibration and sky subtraction.
+.IP
+The parameters are set for a particular Argus configuration and different
+configurations may use different flat fields, arcs, and aperture
+identification tables.
+.IP [3]
+Run the task.  This may be repeated multiple times with different
+observations and the task will generally only do the setup steps
+once and only process new images.  Queries presented during the
+execution for various interactive operations may be answered with
+"yes", "no", "YES", or "NO".  The lower case responses apply just
+to that query while the upper case responses apply to all further
+such queries during the execution and no further queries of that
+type will be made.
+.IP [4]
+The apertures are defined using the specified aperture reference image.
+The spectra are found automatically and apertures assigned based on
+task parameters and the aperture identification table.  Unassigned
+fibers may have a negative beam number and will be ignored in subsequent
+processing.  The resize option sets the aperture size to the widths of
+the profiles at a fixed fraction of the peak height.  The interactive
+review of the apertures is recommended.  If the identifications are off
+by a shift the 'o' key is used.  To exit the aperture review type 'q'.
+.IP [5]
+The fiber positions at a series of points along the dispersion are measured
+and a function is fit to these positions.  This may be done interactively to
+adjust the fitting parameters.  Not all fibers need be examined and the "NO"
+response will quit the interactive fitting.  To exit the interactive
+fitting type 'q'.
+.IP [6]
+If scattered light subtraction is to be done the flat field image is
+used to define the scattered light fitting parameters interactively.
+If one is not specified then the aperture reference image is used for
+this purpose.
+
+There are two queries for the interactive fitting.  A graph of the
+data between the defined reference apertures separated by a specified
+buffer distance is first shown.  The function order and type may be
+adjusted.  After quiting with 'q' the user has the option of changing
+the buffer value and returning to the fitting, changing the image line
+or column to check if the fit parameters are satisfactory at other points,
+or to quit and accept the fit parameters.  After fitting all points
+across the dispersion another graph showing the scattered light from
+the individual fits is shown and the smoothing parameters along the
+dispersion may be adjusted.  Upon quiting with 'q' you have the option
+of checking other cuts parallel to the dispersion or quiting and finishing
+the scattered light function smoothing and subtraction.
+
+If there is a throughput image then this is corrected for scattered light
+noninteractively using the previous fitting parameters.
+.IP [7]
+If flat fielding is to be done the flat field spectra are extracted.  The
+average spectrum over all fibers is determined and a function is fit
+interactively (exit with 'q').  This function is generally of sufficiently
+high order that the overall shape is well fit.  This function is then used
+to normalize the individual flat field spectra.  If a throughput image, a
+sky flat, is specified then the total sky counts through each fiber are
+used to correct the total flat field counts.  Alternatively, a separately
+derived throughput file can be used for specifying throughput corrections.
+If neither type of throughput is used the flat field also provides the
+throughput correction.  The final response spectra are normalized to a unit
+mean over all fibers.  The relative average throughput for each fiber is
+recorded in the log and possibly printed to the terminal.
+.IP [8]
+If dispersion correction is selected the first arc in the arc list is
+extracted.  The middle fiber is used to identify the arc lines and define
+the dispersion function using the task \fBautoidentify\fR.  The
+\fIcrval\fR and \fIcdelt\fR parameters are used in the automatic
+identification.  Whether or not the automatic identification is
+successful you will be shown the result of the arc line identification.
+If the automatic identification is not successful identify a few arc
+lines with 'm' and use the 'l' line list identification command to
+automatically add additional lines and fit the dispersion function.  Check
+the quality of the dispersion function fit with 'f'.  When satisfied exit
+with 'q'.
+.IP [9]
+The remaining fibers are automatically reidentified.  You have the option
+to review the line identifications and dispersion function for each fiber
+and interactively add or delete arc lines and change fitting parameters.
+This can be done selectively, such as when the reported RMS increases
+significantly.
+.IP [10]
+If the spectra are to be resampled to a linear dispersion system
+(which will be the same for all spectra) default dispersion parameters
+are printed and you are allowed to adjust these as desired.
+.IP [11]
+If the sky line alignment option is selected and the sky lines have not
+been identified for a particular aperture identification table then you are
+asked to mark one or more sky lines.  You may simply accept the wavelengths
+of these lines as defined by the dispersion solution for this spectrum and
+fiber or you may specify knowns wavelengths for the lines. These lines will
+be reidentified in all object spectra extracted and a mean zeropoint shift
+will be added to the dispersion solution.  This has the effect of aligning
+these lines to optimize sky subtraction.
+.IP [12]
+The object spectra are now automatically scattered light subtracted,
+ extracted, flat fielded, and dispersion corrected.
+.IP [13]
+When sky subtracting, the individual sky spectra may be reviewed and some
+spectra eliminated using the 'd' key.  The last deleted spectrum may be
+recovered with the 'e' key.  After exiting the review with 'q' you are
+asked for the combining option.  The type of combining is dictated by the
+number of sky fibers.
+.IP [14]
+The option to examine the final spectra with \fBsplot\fR may be given.
+To exit type 'q'.
+.IP [15]
+If scattered light is subtracted from the input data a copy of the
+original image is made by appending "noscat" to the image name.
+If the data are reprocessed with the \fIredo\fR flag the original
+image will be used again to allow modification of the scattered
+light parameters.
+
+The final spectra will have the same name as the original 2D images
+with a ".ms" extension added.  The flat field and arc spectra may
+also have part of the aperture identification table name, if used, added to
+allow different configurations to use the same 2D flat field and arcs
+but with different aperture definitions.  If using the sky alignment
+option an image "align" with the aperture identification table name
+applied will also be created.
+.NH
+Spectra and Data Files
+.LP
+The basic input consists of Argus object and
+calibration spectra stored as IRAF images.
+The type of image format is defined by the
+environment parameter \fIimtype\fR.  Only images with that extension will
+be processed and created.
+The raw CCD images must
+be processed to remove overscan, bias, and dark count effects.  This
+is generally done using the \fBccdred\fR package.
+The \fBdoargus\fR task will abort if the image header keyword CCDPROC,
+which is added by \fBccdproc\fR, is missing.  If the data processed outside
+of the IRAF \fBccdred\fR package then a dummy CCDPROC keyword should be
+added to the image headers; say with \fBhedit\fR.
+ Flat fielding is
+generally not done at this stage but as part of \fBdoargus\fR.
+If flat fielding is done as part of the basic CCD processing then
+a flattened flat field, blank sky observation, or throughput file
+should still be created for applying fiber throughput corrections.
+.LP
+The task \fBdoargus\fR uses several types of calibration spectra.  These
+are flat fields, blank sky flat fields, comparison lamp spectra, and auxiliary
+mercury line (from the dome lights) or sky line spectra.  The flat field,
+throughput image or file, and auxiliary emission line spectra are optional.
+If a flat field is used then the sky flat
+or throughput file is optional assuming the flat field has the same fiber
+illumination.  It is legal to specify only a throughput image or file and
+leave the flat field blank in order to simply apply a throughput
+correction.  Because only the total counts through each fiber are used from
+a throughput image, sky flat exposures need not be of high signal per
+pixel.
+.LP
+There are two types of dispersion calibration methods.  One is to take arc
+calibration exposures through all fibers periodically and apply the
+dispersion function derived from one or interpolated between pairs to the
+object fibers.  This is the usual method with Argus.
+A second (uncommon) method is to \fIauxiliary
+line spectra\fR such as lines in the dome lights or sky lines to monitor
+shifts relative to a few actual arc exposures.  The main reason to do this
+is if taking arc exposures through all fibers is inconvenient.
+.LP
+The assignment of arc or auxiliary line calibration exposures to object
+exposures is generally done by selecting the nearest in time and
+interpolating.  There are other options possible which are described under
+the task \fBrefspectra\fR.  The most general option is to define a table
+giving the object image name and the one or two arc spectra to be assigned
+to that object.  That file is called an \fIarc assignment table\fR and it
+is one of the optional setup files which can used with \fBdoargus\fR.
+.LP
+The first step in the processing is identifying the spectra in the images.
+The default method is to use the fact that object and sky fibers alternate
+and assign sequential numbers to the fibers so the sky fibers are the
+even aperture numbers and the object fibers are the odd aperture numbers.
+In this case the beam numbers are not used and are the same as the
+aperture numbers and there are no object identifications associated with the
+spectra.
+.LP
+A very useful, optional, setup parameter is an \fIaperture identification
+table\fR.  The table contains information about the fiber assignments
+including object titles.  The table is either a text file or an image
+containing the keywords SLFIB.  An aperture identification file contains
+lines consisting of an aperture number, a beam number, and an object
+identification.  In an image the SLFIB keywords contain the aperture
+number, the beam numbers, optional right ascension and declination, and a
+title.  The aperture identification information must be in the same order
+as the fibers in the image.  The aperture number may be any unique number
+but it is recommended that the normal sequential fiber numbers be used.
+The beam number may be used to flag object or sky spectra or simply be the
+same as the aperture number.  The object identifications are optional but
+it is good practice to include them so that the data will contain the
+object information independent of other records.  Figure 1 shows an example
+of a file for a configuration called LMC123.
+
+.ce
+Figure 1: Example Aperture Identification File
+
+.V1
+    cl> type LMC124
+    1 1 143
+    2 0 sky
+    3 1 121
+       .
+       .
+       .
+    47 1 s92
+    48 0 sky
+.V2
+
+Note the identification of the sky fibers with beam number 0 and the
+object fibers with 1.  Any broken fibers should be included and
+identified by a different beam number, say beam number -1, to give the
+automatic spectrum finding operation the best chance to make the
+correct identifications.  Naturally the identification table will vary
+for each configuration.
+Additional information about the aperture identification
+file may be found in the description of the task \fBapfind\fR.
+.LP
+The final reduced spectra are recorded in two or three dimensional IRAF
+images.  The images have the same name as the original images with an added
+".ms" extension.  Each line in the reduced image is a one dimensional
+spectrum with associated aperture, wavelength, and identification
+information.  When the \f(CWextras\fR parameter is set the lines in the
+third dimension contain additional information (see
+\fBapsum\fR for further details).  These spectral formats are accepted by the
+one dimensional spectroscopy tools such as the plotting tasks \fBsplot\fR
+and \fBspecplot\fR.  The special task \fBscopy\fR may be used to extract
+specific apertures or to change format to individual one dimensional
+images.
+.NH
+Package Parameters
+.LP
+The \fBargus\fR package parameters, shown in Figure 1, set parameters
+affecting all the tasks in the package.
+.KS
+.V1
+
+.ce
+Figure 1: Package Parameter Set for ARGUS
+
+                           I R A F
+            Image Reduction and Analysis Facility
+PACKAGE = imred
+   TASK = argus
+
+(dispaxi=            2) Image axis for 2D images
+(observa=  observatory) Observatory of data
+(interp =        poly5) Interpolation type
+
+(databas=     database) Database
+(verbose=           no) Verbose output?
+(logfile=      logfile) Log file
+(plotfil=             ) Plot file
+
+(records=             )
+(version= ARGUS V1: January 1992)
+
+.KE
+.V2
+The dispersion axis parameter defines the image axis along which the
+dispersion runs.  This is used if the image header doesn't define the
+dispersion axis with the DISPAXIS keyword.
+The observatory parameter is only required
+for data taken with fiber instruments other than Argus.
+The spectrum interpolation type might be changed to "sinc" but
+with the cautions given in \fBonedspec.package\fR.
+The other parameters define the standard I/O functions.
+The verbose parameter selects whether to print everything which goes
+into the log file on the terminal.  It is useful for monitoring
+what the \fBdoargus\fR task does.  The log and plot files are useful for
+keeping a record of the processing.  A log file is highly recommended.
+A plot file provides a record of apertures, traces, and extracted spectra
+but can become quite large.
+The plotfile is most conveniently viewed and printed with \fBgkimosaic\fR.
+.NH
+Processing Parameters
+.LP
+The \fBdoargus\fR parameters are shown in Figure 2.
+.KS
+.V1
+
+.ce
+Figure 2: Parameter Set for DOARGUS
+
+                           I R A F
+            Image Reduction and Analysis Facility
+PACKAGE = argus
+   TASK = doargus
+
+objects =               List of object spectra
+(apref  =             ) Aperture reference spectrum
+(flat   =             ) Flat field spectrum
+(through=             ) Throughput file or image (optional)
+(arcs1  =             ) List of arc spectra
+(arcs2  =             ) List of shift arc spectra
+(arcrepl=             ) Special aperture replacements
+(arctabl=             ) Arc assignment table (optional)
+
+.KE
+.V1
+(readnoi=      RDNOISE) Read out noise sigma (photons)
+(gain   =         GAIN) Photon gain (photons/data number)
+(datamax=        INDEF) Max data value / cosmic ray threshold
+(fibers =           97) Number of fibers
+(width  =          12.) Width of profiles (pixels)
+(minsep =           8.) Minimum separation between fibers (pixels)
+(maxsep =          15.) Maximum separation between fibers (pixels)
+(apidtab=             ) Aperture identifications
+(crval  =        INDEF) Approximate wavelength
+(cdelt  =        INDEF) Approximate dispersion
+(objaps =             ) Object apertures
+(skyaps =             ) Sky apertures
+(arcaps =             ) Arc apertures
+(objbeam=          0,1) Object beam numbers
+(skybeam=            0) Sky beam numbers
+(arcbeam=             ) Arc beam numbers
+
+(scatter=           no) Subtract scattered light?
+(fitflat=          yes) Fit and ratio flat field spectrum?
+(clean  =          yes) Detect and replace bad pixels?
+(dispcor=          yes) Dispersion correct spectra?
+(savearc=          yes) Save simultaneous arc apertures?
+(skysubt=          yes) Subtract sky?
+(skyedit=          yes) Edit the sky spectra?
+(savesky=          yes) Save sky spectra?
+(splot  =           no) Plot the final spectrum?
+(redo   =           no) Redo operations if previously done?
+(update =          yes) Update spectra if cal data changes?
+(batch  =           no) Extract objects in batch?
+(listonl=           no) List steps but don't process?
+
+(params =             ) Algorithm parameters
+
+.V2
+The list of objects and arcs can be @ files if desired.  The aperture
+reference spectrum is usually the same as the flat field spectrum though it
+could be any exposure with enough signal to accurately define the positions
+and trace the spectra.  The first list of arcs are the standard Th-Ar or
+HeNeAr comparison arc spectra (they must all be of the same type).  The
+second list of arcs are the auxiliary emission line exposures mentioned
+previously.
+.LP
+The detector read out noise and gain are used for cleaning and variance
+(optimal) extraction.
+The variance
+weighting and cosmic-ray cleanning are sensitive to extremely strong
+cosmic-rays; ones which are hundreds of times brighter than the
+spectrum.  The \fIdatamax\fR is used to set an upper limit for any
+real data.  Any pixels above this value will be flagged as cosmic-rays
+and will not affect the extractions.
+The dispersion axis defines the wavelength direction of spectra in
+the image if not defined in the image header by the keyword DISPAXIS.  The
+width and separation parameters define the dimensions (in pixels) of the
+spectra (fiber profile) across the dispersion.  The width parameter
+primarily affects the centering.  The maximum separation parameter is
+important if missing spectra are to
+be correctly skipped.  The number of fibers can be left at the default
+and the task will try to account for unassigned or missing fibers.
+However, this may lead to occasional incorrect
+identifications so it is recommended that only the true number of
+fibers be specified.  The aperture identification table was described
+earlier.
+.LP
+The approximate central wavelength and dispersion are used for the
+automatic identification of the arc reference.  They may be specified
+as image header keywords or values.  The INDEF values search the
+entire range of the coordinate reference file but the automatic
+line identification algorithm works much better and faster if
+approximate values are given.
+.LP
+The task needs to know which fibers are object and which are sky
+if sky subtraction is to be done.  One could explicitly
+give the aperture numbers but the recommended way is to use the default
+of selecting every second fiber as sky.  If no list of aperture or beam
+numbers is given
+then all apertures or beam numbers are selected.  Sky subtracted sky
+spectra are useful for evaluating the sky subtraction.  Since only
+the spectra identified as objects are sky subtracted one can exclude
+fibers from the sky subtraction.  For example, to eliminate the sky
+spectra from the final results the \fIobjaps\fR parameter could be
+set to "1x2".  All other fibers will remain in the extracted spectra
+but will not be sky subtracted.
+.LP
+The next set of parameters select the processing steps and options.  The
+scattered light option allows fitting and subtracting a scattered light
+surface from the input object and flat field.  If there is significant
+scattered light which is not subtracted the fiber throughput correction
+will not be accurate.  The
+flat fitting option allows fitting and removing the overall shape of the
+flat field spectra while preserving the pixel-to-pixel response
+corrections.  This is useful for maintaining the approximate object count
+levels and not introducing the reciprocal of the flat field spectrum into
+the object spectra.  The \f(CWclean\fR option invokes a profile fitting and
+deviant point rejection algorithm as well as a variance weighting of points
+in the aperture.  These options require knowing the effective (i.e.
+accounting for any image combining) read out noise and gain.  For a
+discussion of cleaning and variance weighted extraction see
+\fBapvariance\fR and \fBapprofiles\fR.
+.LP
+The dispersion correction option selects whether to extract arc spectra,
+determine a dispersion function, assign them to the object spectra, and,
+possibly, resample the spectra to a linear (or log-linear) wavelength
+scale.  If simultaneous arc fibers are defined there is an option to delete
+them from the final spectra when they are no longer needed.
+.LP
+The sky alignment option allows applying a zeropoint dispersion shift
+to all fibers based on one or more sky lines.  This requires all fibers
+to have the sky lines visible.  When there are sky lines this will
+improve the sky subtraction if there is a systematic error in the
+fiber illumination between the sky and the arc calibration.
+.LP
+The sky subtraction option selects whether to combine the sky fiber spectra
+and subtract this sky from the object fiber spectra.  It is also possible
+to subtract the sky and object fibers by pairs.  \fIDispersion
+correction and sky subtraction are independent operations.\fR  This means
+that if dispersion correction is not done then the sky subtraction will be
+done with respect to pixel coordinates.  This might be desirable in some
+quick look cases though it is incorrect for final reductions.
+.LP
+The sky subtraction option has two additional options.  The individual sky
+spectra may be examined and contaminated spectra deleted interactively
+before combining.  This can be a useful feature in crowded regions.  The
+final combined sky spectrum (or individual skys if subtracting by
+pairs) may be saved for later inspection in an image
+with the spectrum name prefixed by \fBsky\fR.
+.LP
+After a spectrum has been processed it is possible to examine the results
+interactively using the \fBsplot\fR tasks.  This option has a query which
+may be turned off with "YES" or "NO" if there are multiple spectra to be
+processed.
+.LP
+Generally once a spectrum has been processed it will not be reprocessed if
+specified as an input spectrum.  However, changes to the underlying
+calibration data can cause such spectra to be reprocessed if the
+\f(CWupdate\fR flag is set.  The changes which will cause an update are a new
+aperture identification table, a new reference image, new flat fields, and a
+new arc reference.  If all input spectra are to be processed regardless of
+previous processing the \f(CWredo\fR flag may be used.  Note that
+reprocessing clobbers the previously processed output spectra.
+.LP
+The \f(CWbatch\fR processing option allows object spectra to be processed as
+a background or batch job.  This will only occur if sky spectra editing and
+\fBsplot\fR review (interactive operations) are turned off, either when the
+task is run or by responding with "NO" to the queries during processing.
+.LP
+The \f(CWlistonly\fR option prints a summary of the processing steps which
+will be performed on the input spectra without actually doing anything.
+This is useful for verifying which spectra will be affected if the input
+list contains previously processed spectra.  The listing does not include
+any arc spectra which may be extracted to dispersion calibrate an object
+spectrum.
+.LP
+The last parameter (excluding the task mode parameter) points to another
+parameter set for the algorithm parameters.  The way \fBdoargus\fR works
+this may not have any value and the parameter set \fBparams\fR is always
+used.  The algorithm parameters are discussed further in the next section.
+.NH
+Algorithms and Algorithm Parameters
+.LP
+This section summarizes the various algorithms used by the \fBdoargus\fR
+task and the parameters which control and modify the algorithms.  The
+algorithm parameters available to the user are collected in the parameter
+set \fBparams\fR.  These parameters are taken from the various general
+purpose tasks used by the \fBdoargus\fR processing task.  Additional
+information about these parameters and algorithms may be found in the help
+for the actual task executed.  These tasks are identified in the parameter
+section listing in parenthesis.  The aim of this parameter set organization
+is to collect all the algorithm parameters in one place separate from the
+processing parameters and include only those which are relevant for
+Argus.  The parameter values can be changed from the
+defaults by using the parameter editor,
+.V1
+
+	cl> epar params
+
+.V2
+or simple typing \f(CWparams\fR.  The parameter editor can also be
+entered when editing the \fBdoargus\fR parameters by typing \f(CW:e
+params\fR or simply \f(CW:e\fR if positioned at the \f(CWparams\fR
+parameter.  Figure 3 shows the parameters set.
+.KS
+.V1
+
+.ce
+Figure 3: Algorithm Parameter Set
+
+                           I R A F
+            Image Reduction and Analysis Facility
+PACKAGE = argus
+   TASK = params
+
+(line   =        INDEF) Default dispersion line
+(nsum   =           10) Number of dispersion lines to sum
+(order  =   decreasing) Order of apertures
+(extras =           no) Extract sky, sigma, etc.?
+
+                        -- DEFAULT APERTURE LIMITS --
+(lower  =          -5.) Lower aperture limit relative to center
+(upper  =           5.) Upper aperture limit relative to center
+
+                        -- AUTOMATIC APERTURE RESIZING PARAMETERS --
+(ylevel =         0.05) Fraction of peak or intensity for resizing
+
+.KE
+.KS
+.V1
+                        -- TRACE PARAMETERS --
+(t_step =           10) Tracing step
+(t_funct=      spline3) Trace fitting function
+(t_order=            3) Trace fitting function order
+(t_niter=            1) Trace rejection iterations
+(t_low  =           3.) Trace lower rejection sigma
+(t_high =           3.) Trace upper rejection sigma
+
+.KE
+.KS
+.V1
+                        -- SCATTERED LIGHT PARAMETERS --
+(buffer =           1.) Buffer distance from apertures
+(apscat1=             ) Fitting parameters across the dispersion
+(apscat2=             ) Fitting parameters along the dispersion
+
+.KE
+.KS
+.V1
+                        -- APERTURE EXTRACTION PARAMETERS --
+(weights=         none) Extraction weights (none|variance)
+(pfit   =        fit1d) Profile fitting algorithm (fit1d|fit2d)
+(lsigma =           3.) Lower rejection threshold
+(usigma =           3.) Upper rejection threshold
+(nsubaps=            1) Number of subapertures
+
+.KE
+.KS
+.V1
+                        -- FLAT FIELD FUNCTION FITTING PARAMETERS --
+(f_inter=          yes) Fit flat field interactively?
+(f_funct=      spline3) Fitting function
+(f_order=           10) Fitting function order
+
+.KE
+.KS
+.V1
+                        -- ARC DISPERSION FUNCTION PARAMETERS --
+(coordli=linelists$idhenear.dat) Line list
+(match  =          10.) Line list matching limit in Angstroms
+(fwidth =           4.) Arc line widths in pixels
+(cradius=          10.) Centering radius in pixels
+(i_funct=      spline3) Coordinate function
+(i_order=            3) Order of dispersion function
+(i_niter=            2) Rejection iterations
+(i_low  =           3.) Lower rejection sigma
+(i_high =           3.) Upper rejection sigma
+(refit  =          yes) Refit coordinate function when reidentifying?
+(addfeat=           no) Add features when reidentifying?
+
+.KE
+.KS
+.V1
+                        -- AUTOMATIC ARC ASSIGNMENT PARAMETERS --
+(select =       interp) Selection method for reference spectra
+(sort   =           jd) Sort key
+(group  =          ljd) Group key
+(time   =           no) Is sort key a time?
+(timewra=          17.) Time wrap point for time sorting
+
+.KE
+.KS
+.V1
+                        -- DISPERSION CORRECTION PARAMETERS --
+(lineari=          yes) Linearize (interpolate) spectra?
+(log    =           no) Logarithmic wavelength scale?
+(flux   =          yes) Conserve flux?
+
+.KE
+.KS
+.V1
+                        -- SKY SUBTRACTION PARAMETERS --
+(combine=      average) Type of combine operation
+(reject =    avsigclip) Sky rejection option
+(scale  =         none) Sky scaling option
+
+.KE
+.V2
+.NH 2
+Extraction
+.LP
+The identification of the spectra in the two dimensional images and their
+scattered light subtraction and extraction to one dimensional spectra
+in multispec format is accomplished
+using the tasks from the \fBapextract\fR package.  The first parameters
+through \f(CWnsubaps\fR control the extractions.
+.LP
+The dispersion line is that used for finding the spectra, for plotting in
+the aperture editor, and as the starting point for tracing.  The default
+value of \fBINDEF\fR selects the middle of the image.  The aperture
+finding, adjusting, editing, and tracing operations also allow summing a
+number of dispersion lines to improve the signal.  The number of lines is
+set by the \f(CWnsum\fR parameter.
+.LP
+The order parameter defines whether the order of the aperture
+identifications in the aperture identification table (or the default
+sequential numbers if no file is used) is in the same sense as the image
+coordinates (increasing) or the opposite sense (decreasing).  If the
+aperture identifications turn out to be opposite to what is desired when
+viewed in the aperture editing graph then simply change this parameter.
+.LP
+The basic data output by the spectral extraction routines are the one
+dimensional spectra.  Additional information may be output when the
+\f(CWextras\fR option is selected and the cleaning or variance weighting
+options are also selected.  In this case a three dimensional image is
+produced with the first element of the third dimension being the cleaned
+and/or weighted spectra, the second element being the uncleaned and
+unweighted spectra, and the third element being an estimate of the sigma
+of each pixel in the extracted spectrum.  Currently the sigma data is not
+used by any other tasks and is only for reference.
+.LP
+The initial step of finding the fiber spectra in the aperture reference
+image consists of identifying the peaks in a cut across the dispersion,
+eliminating those which are closer to each other than the \f(CWminsep\fR
+distance, and then keeping the specified \f(CWnfibers\fR highest peaks.  The
+centers of the profiles are determined using the \fBcenter1d\fR algorithm
+which uses the \f(CWwidth\fR parameter.
+.LP
+Apertures are then assigned to each spectrum.  The initial edges of the
+aperture relative to the center are defined by the \f(CWlower\fR and
+\f(CWupper\fR parameters.
+.LP
+The initial apertures are the same for all spectra but they can each be
+automatically resized.  The automatic resizing sets the aperture limits
+at a fraction of the peak relative to the interfiber minimum.
+The default \f(CWylevel\fR is to resize the apertures to 5% of the peak.
+See the description for the task \fBapresize\fR for further details.
+.LP
+The user is given the opportunity to graphically review and adjust the
+aperture definitions.  This is recommended
+and it is fundamentally important that the correct aperture/beam numbers
+be associated with the proper fibers;
+otherwise the spectrum
+identifications will not be for the objects they say.  An important command in
+this regard is the 'o' key which allows reordering the identifications.
+This is required if the first
+fiber is actually missing since the initial assignment begins with the
+first spectrum found.  The
+aperture editor is a very powerful tool and is described in detail as
+\fBapedit\fR.
+.LP
+The next set of parameters control the tracing and function fitting of the
+aperture reference positions along the dispersion direction.  The position
+of a spectrum across the dispersion is determined by the centering
+algorithm (see \fBcenter1d\fR) at a series of evenly spaced steps, given by
+the parameter \f(CWt_step\fR, along the dispersion.  The step size should be
+fine enough to follow position changes but it is not necessary to measure
+every point.  The fitted points may jump around a little bit due to noise
+and cosmic rays even when summing a number of lines.  Thus, a smooth
+function is fit.  The function type, order, and iterative rejection of
+deviant points is controlled by the other trace parameters.  For more
+discussion consult the help pages for \fBaptrace\fR and \fBicfit\fR.  The
+default is to fit a cubic spline of three pieces with a single iteration of
+3 sigma rejection.
+.LP
+The actual extraction of the spectra by summing across the aperture at each
+point along the dispersion is controlled by the next set of parameters.
+The default extraction simply sums the pixels using partial pixels at the
+ends.  The options allow selection of a weighted sum based on a Poisson
+variance model using the \f(CWreadnoise\fR and \f(CWgain\fR detector
+parameters.  Note that if the \f(CWclean\fR option is selected the variance
+weighted extraction is used regardless of the \f(CWweights\fR parameter.  The
+sigma thresholds for cleaning are also set in the \fBparams\fR parameters.
+For more on the variance weighted extraction and cleaning see
+\fBapvariance\fR and \fBapprofiles\fR as well as \fBapsum\fR.
+.LP
+The last parameter, \f(CWnsubaps\fR, is used only in special cases when it is
+desired to subdivide the fiber profiles into subapertures prior to
+dispersion correction.  After dispersion correction the subapertures are
+then added together.  The purpose of this is to correct for wavelength
+shifts across a fiber.
+.NH 2
+Scattered Light Subtraction
+.LP
+Scattered light may be subtracted from the input two dimensional image as
+the first step.  This is done using the algorithm described in
+\fBapscatter\fR.  This can be important if there is significant scattered
+light since the flat field/throughput correction will otherwise be
+incorrect.  The algorithm consists of fitting a function to the data
+outside the defined apertures by a specified \fIbuffer\fR at each line or
+column across the dispersion.  The function fitting parameters are the same
+at each line.  Because the fitted functions are independent at each line or
+column a second set of one dimensional functions are fit parallel to the
+dispersion using the evaluated fit values from the cross-dispersion step.
+This produces a smooth scattered light surface which is finally subtracted
+from the input image.  Again the function fitting parameters are the
+same at each line or column though they may be different than the parameters
+used to fit across the dispersion.
+.LP
+The first time the task is run with a particular flat field (or aperture
+reference image if no flat field is used) the scattered light fitting
+parameters are set interactively using that image.  The interactive step
+selects a particular line or column upon which the fitting is done
+interactively with the \fBicfit\fR commands.  A query is first issued
+which allows skipping this interactive stage.  Note that the interactive
+fitting is only for defining the fitting functions and orders.  When
+the graphical \fBicfit\fR fitting is exited (with 'q') there is a second prompt
+allowing you to change the buffer distance (in the first cross-dispersion
+stage) from the apertures, change the line/column, or finally quit.
+.LP
+The initial fitting parameters and the final set parameters are recorded
+in the \fBapscat1\fR and \fBapscat2\fR hidden parameter sets.  These
+parameters are then used automatically for every subsequent image
+which is scattered light corrected.
+.LP
+The scattered light subtraction modifies the input 2D images.  To preserve
+the original data a copy of the original image is made with the same
+root name and the word "noscat" appended.  The scattered light subtracted
+images will have the header keyword "APSCATTE" which is how the task
+avoids repeating the scattered light subtraction during any reprocessing.
+However if the \fIredo\fR option is selected the scattered light subtraction
+will also be redone by first restoring the "noscat" images to the original
+input names.
+.NH 2
+Flat Field and Fiber Throughput Corrections
+.LP
+Flat field corrections may be made during the basic CCD processing; i.e.
+direct division by the two dimensional flat field observation.  In that
+case do not specify a flat field spectrum; use the null string "".  The
+\fBdoargus\fR task provides an alternative flat field response correction
+based on division of the extracted object spectra by the extracted flat field
+spectra.  A discussion of the theory and merits of flat fielding directly
+verses using the extracted spectra will not be made here.  The
+\fBdoargus\fR flat fielding algorithm is the \fIrecommended\fR method for
+flat fielding since it works well and is not subject to the many problems
+involved in two dimensional flat fielding.
+.LP
+In addition to correcting for pixel-to-pixel response the flat field step
+also corrects for differences in the fiber throughput.  Thus, even if the
+pixel-to-pixel flat field corrections have been made in some other way it
+is desirable to use a sky or dome flat observation for determining a fiber
+throughput correction.  Alternatively, a separately derived throughput
+file may be specified.  This file consists of the aperture numbers
+(the same as used for the aperture reference) and relative throughput
+numbers.
+.LP
+The first step is extraction of the flat field spectrum, if specified,
+using the reference apertures.  Only one flat field is allowed so if
+multiple flat fields are required the data must be reduced in groups.
+After extraction one or more corrections are applied.  If the \f(CWfitflat\fR
+option is selected (the default) the extracted flat field spectra are
+averaged together and a smooth function is fit.  The default fitting
+function and order are given by the parameters \f(CWf_function\fR and
+\f(CWf_order\fR.  If the parameter \f(CWf_interactive\fR is "yes" then the
+fitting is done interactively using the \fBfit1d\fR task which uses the
+\fBicfit\fR interactive fitting commands.
+.LP
+The fitted function is divided into the individual flat field spectra to
+remove the basic shape of the spectrum while maintaining the relative
+individual pixel responses and any fiber to fiber differences.  This step
+avoids introducing the flat field spectrum shape into the object spectra
+and closely preserves the object counts.
+.LP
+If a throughput image is available (an observation of blank sky
+usually at twilight) it is extracted.  If no flat field is used the average
+signal through each fiber is computed and this becomes the response
+normalization function.  Note that a dome flat may be used in place of a
+sky in the sky flat field parameter for producing throughput only
+corrections.  If a flat field is specified then each sky spectrum is
+divided by the appropriate flat field spectrum.  The total counts through
+each fiber are multiplied into the flat field spectrum thus making the sky
+throughput of each fiber the same.  This correction is important if the
+illumination of the fibers differs between the flat field source and the
+sky.  Since only the total counts are required the sky or dome flat field
+spectra need not be particularly strong though care must be taken to avoid
+objects.
+.LP
+Instead of a sky flat or other throughput image a separately derived
+throughput file may be used.  It may be used with or without a
+flat field.
+.LP
+The final step is to normalize the flat field spectra by the mean counts of
+all the fibers.  This normalization step is simply to preserve the average
+counts of the extracted object and arc spectra after division by the
+response spectra.  The final relative throughput values are recorded in the
+log and possibly printed on the terminal.
+.LP
+These flat field response steps and algorithm are available as a separate
+task called \fBmsresp1d\fR.
+.NH 2
+Dispersion Correction
+.LP
+Dispersion corrections are applied to the extracted spectra if the
+\fBdispcor\fR parameter is set.  This can be a complicated process which
+the \fBdoargus\fR task tries to simplify for you.  There are three basic
+steps involved; determining the dispersion functions relating pixel
+position to wavelength, assigning the appropriate dispersion function to a
+particular observation, and resampling the spectra to evenly spaced pixels
+in wavelength.
+.LP
+The comparison arc spectra are used to define dispersion functions for the
+fibers using the tasks \fBautoidentify\fR and \fBreidentify\fR.  The
+interactive \fBautoidentify\fR task is only used on the central fiber of the
+first arc spectrum to define the basic reference dispersion solution from
+which all other fibers and arc spectra are automatically derived using
+\fBreidentify\fR. \fBAutoidentify\fR attempts to automatically identify
+the arc lines using the \fIcrval\fR and \fIcdelt\fR parameters.  Whether or
+not it is successful the user is presented with the interactive
+identification graph.  The automatic identifications can be reviewed and a
+new solution or corrections to the automatic solution may be performed.
+.LP
+The set of arc dispersion function parameters are from \fBautoidentify\fR and
+\fBreidentify\fR.  The parameters define a line list for use in
+automatically assigning wavelengths to arc lines, a parameter controlling
+the width of the centering window (which should match the base line
+widths), the dispersion function type and order, parameters to exclude bad
+lines from function fits, and parameters defining whether to refit the
+dispersion function, as opposed to simply determining a zero point shift,
+and the addition of new lines from the line list when reidentifying
+additional arc spectra.  The defaults should generally be adequate and the
+dispersion function fitting parameters may be altered interactively.  One
+should consult the help for the two tasks for additional details of these
+parameters and the operation of \fBautoidentify\fR.
+.LP
+Generally, taking a number of comparison arc lamp exposures interspersed
+with the program spectra is sufficient to accurately dispersion calibrate
+Argus spectra. Dispersion functions are
+determined independently for each fiber of each arc image and then assigned
+to the matching fibers in the program object observations.  The assignment
+consists of selecting one or two arc images to calibrate each object
+image.
+.LP
+However, there is another calibration option which may be of interest.
+This option uses auxiliary line spectra, such as from dome lights or night
+sky lines, to monitor wavelength zero point shifts which are added to the
+basic dispersion function derived from a single reference arc.  Initially
+one of the auxiliary fiber spectra is plotted interactively by
+\fBidentify\fR with the reference dispersion function for the appropriate
+fiber.  The user marks one or more lines which will be used to compute zero
+point wavelength shifts in the dispersion functions automatically.  In this
+case it is auxiliary arc images which are assigned to particular objects.
+.LP
+The arc or auxiliary line image assignments may be done either explicitly with
+an arc assignment
+table (parameter \f(CWarctable\fR) or based on a header parameter.  The task
+used is \fBrefspectra\fR and the user should consult this task if the
+default behavior is not what is desired.  The default is to interpolate
+linearly between the nearest arcs based on the Julian date (corrected to
+the middle of the exposure).  The Julian date and a local Julian day number
+(the day number at local noon) are computed automatically by the task
+\fBsetjd\fR and recorded in the image headers under the keywords JD and
+LJD.  In addition the universal time at the middle of the exposure, keyword
+UTMIDDLE, is computed by the task \fBsetairmass\fR and this may also be used
+for ordering the arc and object observations.
+.LP
+An optional step is to use sky lines in the spectra to compute a zeropoint
+dispersion shift that will align the sky lines.  This may improve sky
+subtraction if the illumination is not the same between the arc calibration
+and the sky.  When selected the object spectrum is dispersion corrected
+using a non-linear dispersion function to avoid resampling the spectrum.
+The sky lines are then reidentified in wavelength space from a template
+list of sky lines.  The mean shift in the lines for each fiber relative to
+the template in that fiber is computed to give the zeropoint shift.  The
+database file is created when the first object is extracted.  You are asked
+to mark the sky lines in one fiber and then the lines are automatically
+reidentified in all other fibers.  Note that this technique requires the
+sky lines be found in all fibers.
+.LP
+The last step of dispersion correction (resampling the spectrum to evenly
+spaced pixels in wavelength) is optional and relatively straightforward.
+If the \f(CWlinearize\fR parameter is no then the spectra are not resampled
+and the nonlinear dispersion information is recorded in the image header.
+Other IRAF tasks (the coordinate description is specific to IRAF) will use
+this information whenever wavelengths are needed.  If linearizing is
+selected a linear dispersion relation, either linear in the wavelength or
+the log of the wavelength, is defined once and applied to every extracted
+spectrum.  The resampling algorithm  parameters allow selecting the
+interpolation function type, whether to conserve flux per pixel by
+integrating across the extent of the final pixel, and whether to linearize
+to equal linear or logarithmic intervals.  The latter may be appropriate
+for radial velocity studies.  The default is to use a fifth order
+polynomial for interpolation, to conserve flux, and to not use logarithmic
+wavelength bins.  These parameters are described fully in the help for the
+task \fBdispcor\fR which performs the correction.  The interpolation
+function options and the nonlinear dispersion coordinate system is
+described in the help topic \fBonedspec.package\fR.
+.NH 2
+Sky Subtraction
+.LP
+Sky subtraction is selected with the \f(CWskysubtract\fR processing option.
+The sky spectra are selected by their aperture and beam numbers.
+If the \f(CWskyedit\fR
+option is selected the sky spectra are plotted using the task
+\fBspecplot\fR.  By default they are superposed to allow identifying
+spectra with unusually high signal due to object contamination.  To
+eliminate a sky spectrum from consideration point at it with the cursor and
+type 'd'.  The last deleted spectrum may be undeleted with 'e'.  This
+allows recovery of incorrect or accidental deletions.
+.LP
+If the combining option is "none" then the sky and object fibers are
+paired and one sky is subtracted from one object and the saved sky will
+be the individual sky fiber spectra.
+.LP
+However, the usual
+case is to combine the individual skys into a single master sky spectrum
+which is then subtracted from each object spectrum.
+The sky combining algorithm parameters define how the individual sky fiber
+spectra, after interactive editing, are combined before subtraction from
+the object fibers.  The goals of combining are to reduce noise, eliminate
+cosmic-rays, and eliminate fibers with inadvertent objects.  The common
+methods for doing this to use a median and/or a special sigma clipping
+algorithm (see \fBscombine\fR for details).  The scale
+parameter determines whether the individual skys are first scaled to a
+common mode.  The scaling should be used if the throughput is uncertain,
+but in that case you probably did the wrong thing in the throughput
+correction.  If the sky subtraction is done interactively, i.e. with the
+\f(CWskyedit\fR option selected, then after selecting the spectra to be
+combined a query is made for the combining algorithm.  This allows
+modifying the default algorithm based on the number of sky spectra
+selected since the "avsigclip" rejection algorithm requires at least
+three spectra.
+.LP
+The combined sky spectrum is subtracted from only those spectra specified
+by the object aperture and beam numbers.  Other spectra
+are retained unchanged.  One may include the sky spectra as
+object spectra to produce residual sky spectra for analysis.  The combined
+master sky spectra may be saved if the \f(CWsaveskys\fR parameter is set.
+The saved sky is given the name of the object spectrum with the prefix
+"sky".
+.NH
+References
+.NH 2
+IRAF Introductory References
+.LP
+Work is underway on a new introductory guide to IRAF.  Currently, the
+work below is the primary introduction.
+.IP
+P. Shames and D. Tody, \fIA User's Introduction to the IRAF Command
+Language\fR, Central Computer Services, NOAO, 1986.
+.NH 2
+CCD Reductions
+.IP
+F. Valdes, \fIThe IRAF CCD Reduction Package -- CCDRED\fR, Central
+Computer Services, NOAO, 1987.
+.IP
+F. Valdes, \fIUser's Guide to the CCDRED Package\fR, Central
+Computer Services, NOAO, 1988.  Also on-line as \f(CWhelp ccdred.guide\fR.
+.IP
+P. Massey, \fIA User's Guide to CCD Reductions with IRAF\fR, Central
+Computer Services, NOAO, 1989.
+.NH 2
+Aperture Extraction Package
+.IP
+F. Valdes, \fIThe IRAF APEXTRACT Package\fR, Central Computer Services,
+NOAO, 1987 (out-of-date).
+.NH 2
+Task Help References
+.LP
+Each task in the \fBargus\fR package and tasks used by \fBdoargus\fR have
+help pages describing the parameters and task in some detail.  To get
+on-line help type
+.V1
+
+cl> help \fItaskname\fR
+
+.V2
+The output of this command can be piped to \fBlprint\fR to make a printed
+copy.
+
+.V1
+      apall - Extract 1D spectra (all parameters in one task)
+  apdefault - Set the default aperture parameters
+     apedit - Edit apertures interactively
+     apfind - Automatically find spectra and define apertures
+ aprecenter - Recenter apertures
+   apresize - Resize apertures
+      apsum - Extract 1D spectra
+    aptrace - Trace positions of spectra
+
+      bplot - Batch plots of spectra
+  continuum - Fit the continuum in spectra
+    dispcor - Dispersion correct spectra
+     dopcor - Doppler correct spectra
+   identify - Identify features in spectrum for dispersion solution
+   msresp1d - Create 1D response spectra from flat field and sky spectra
+ refspectra - Assign wavelength reference spectra to other spectra
+ reidentify - Automatically identify features in spectra
+ sapertures - Set or change aperture header information
+     sarith - Spectrum arithmetic
+   scombine - Combine spectra having different wavelength ranges
+      scopy - Select and copy apertures in different spectral formats
+ setairmass - Compute effective airmass and middle UT for an exposure
+      setjd - Compute and set Julian dates in images
+      slist - List spectrum header parameters
+   specplot - Stack and plot multiple spectra
+      splot - Preliminary spectral plot/analysis
+
+    doargus - Process ARGUS spectra
+      demos - Demonstrations and tests
+
+	    Additional help topics
+
+   onedspec.package - Package parameters and general description of package
+  apextract.package - Package parameters and general description of package
+ approfiles - Profile determination algorithms
+ apvariance - Extractions, variance weighting, cleaning, and noise model
+   center1d - One dimensional centering algorithm
+      icfit - Interactive one dimensional curve fitting
+.V2
+.SH
+Appendix A:  DOARGUS Parameters
+.LP
+.nr PS 8
+.nr VS 10
+objects
+.LS
+List of object spectra to be processed.  Previously processed spectra are
+ignored unless the \f(CWredo\fR flag is set or the \f(CWupdate\fR flag is set and
+dependent calibration data has changed.  Extracted spectra are ignored.
+.LE
+apref = ""
+.LS
+Aperture reference spectrum.  This spectrum is used to define the basic
+extraction apertures and is typically a flat field spectrum.
+.LE
+flat = "" (optional)
+.LS
+Flat field spectrum.  If specified the one dimensional flat field spectra
+are extracted and used to make flat field calibrations.  If a separate
+throughput file or image is not specified the flat field is also used
+for computing a fiber throughput correction.
+.LE
+throughput = "" (optional)
+.LS
+Throughput file or image.  If an image is specified, typically a blank sky
+observation, the total flux through each fiber is used to correct for fiber
+throughput.  If a file consisting of lines with the aperture number and
+relative throughput is specified then the fiber throughput will be
+corrected by those values.  If neither is specified but a flat field image
+is given it is used to compute the throughput.
+.LE
+arcs1 = "" (at least one if dispersion correcting)
+.LS
+List of primary arc spectra.  These spectra are used to define the dispersion
+functions for each fiber apart from a possible zero point correction made
+with secondary shift spectra or arc calibration fibers in the object spectra.
+One fiber from the first spectrum is used to mark lines and set the dispersion
+function interactively and dispersion functions for all other fibers and
+arc spectra are derived from it.
+.LE
+arcs2 = "" (optional)
+.LS
+List of optional shift arc spectra.  Features in these secondary observations
+are used to supply a wavelength zero point shift through the observing
+sequence.  One type of observation is dome lamps containing characteristic
+emission lines.
+.LE
+arctable = "" (optional) (refspectra)
+.LS
+Table defining arc spectra to be assigned to object
+spectra (see \fBrefspectra\fR).  If not specified an assignment based
+on a header parameter, \f(CWparams.sort\fR, such as the observation time is made.
+.LE
+
+readnoise = "0." (apsum)
+.LS
+Read out noise in photons.  This parameter defines the minimum noise
+sigma.  It is defined in terms of photons (or electrons) and scales
+to the data values through the gain parameter.  A image header keyword
+(case insensitive) may be specified to get the value from the image.
+.LE
+gain = "1." (apsum)
+.LS
+Detector gain or conversion factor between photons/electrons and
+data values.  It is specified as the number of photons per data value.
+A image header keyword (case insensitive) may be specified to get the value
+from the image.
+.LE
+datamax = INDEF (apsum.saturation)
+.LS
+The maximum data value which is not a cosmic ray.
+When cleaning cosmic rays and/or using variance weighted extraction
+very strong cosmic rays (pixel values much larger than the data) can
+cause these operations to behave poorly.  If a value other than INDEF
+is specified then all data pixels in excess of this value will be
+excluded and the algorithms will yield improved results.
+This applies only to the object spectra and not the flat field or
+arc spectra.  For more
+on this see the discussion of the saturation parameter in the
+\fBapextract\fR package.
+.LE
+fibers = 48 (apfind)
+.LS
+Number of fibers.  This number is used during the automatic definition of
+the apertures from the aperture reference spectrum.  It is best if this
+reflects the actual number of fibers which may be found in the aperture
+reference image.  Note that Argus fibers which are unassigned will still
+contain enough light for identification and the aperture identification
+table will be used to eliminate the unassigned fibers.  The interactive
+review of the aperture assignments allows verification and adjustments
+to the automatic aperture definitions.
+.LE
+width = 6. (apedit)
+.LS
+Approximate base full width of the fiber profiles.  This parameter is used
+for the profile centering algorithm.
+.LE
+minsep = 8. (apfind)
+.LS
+Minimum separation between fibers.  Weaker spectra or noise within this
+distance of a stronger spectrum are rejected.
+.LE
+maxsep = 10. (apfind)
+.LS
+Maximum separation between adjacent fibers.  This parameter
+is used to identify missing fibers.  If two adjacent spectra exceed this
+separation then it is assumed that a fiber is missing and the aperture
+identification assignments will be adjusted accordingly.
+.LE
+apidtable = "" (apfind)
+.LS
+Aperture identification table.  This may be either a text file or an
+image.  A text file contains the fiber number, beam number defining object
+(1), sky (0), and arc (2) fibers, and a object title.  An image contains
+the keywords SLFIBnnn with string value consisting of the fiber number,
+beam number, optional right ascension and declination, and an object
+title.  Unassigned and broken fibers (beam of -1)
+should be included in this list since they will automatically be excluded.
+.LE
+crval = INDEF, cdelt = INDEF (autoidentify)
+.LS
+These parameters specify an approximate central wavelength and dispersion.
+They may be specified as numerical values, INDEF, or image header keyword
+names whose values are to be used.
+If both these parameters are INDEF then the automatic identification will
+not be done.
+.LE
+objaps = "", skyaps = "2x2"
+.LS
+List of object and sky aperture numbers.  These are used to
+identify object and sky
+apertures for sky subtraction.  Note sky apertures may be identified as
+both object and sky if one wants to subtract the mean sky from the
+individual sky spectra.  Because the fibers typically alternate
+sky and object the default is to define the sky apertures by their
+aperture numbers and select both object and sky fibers for sky subtraction.
+.LE
+objbeams = "", skybeams = ""
+.LS
+List of object and sky beam numbers.
+The beam numbers are typically the same as the aperture numbers unless
+set in the \fIapidtable\fR.
+.LE
+
+scattered = no (apscatter)
+.LS
+Smooth and subtracted scattered light from the object and flat field
+images.  This operation consists of fitting independent smooth functions
+across the dispersion using data outside the fiber apertures and then
+smoothing the individual fits along the dispersion.  The initial
+flat field, or if none is given the aperture reference image, are
+done interactively to allow setting the fitting parameters.  All
+subsequent subtractions use the same fitting parameters.
+.LE
+fitflat = yes (flat1d)
+.LS
+Fit the composite flat field spectrum by a smooth function and divide each
+flat field spectrum by this function?  This operation removes the average
+spectral signature of the flat field lamp from the sensitivity correction to
+avoid modifying the object fluxes.
+.LE
+clean = yes (apsum)
+.LS
+Detect and correct for bad pixels during extraction?  This is the same
+as the clean option in the \fBapextract\fR package.  If yes this also
+implies variance weighted extraction and requires reasonably good values
+for the readout noise and gain.  In addition the datamax parameters
+can be useful.
+.LE
+dispcor = yes
+.LS
+Dispersion correct spectra?  Depending on the \f(CWparams.linearize\fR
+parameter this may either resample the spectra or insert a dispersion
+function in the image header.
+.LE
+skyalign = no
+.LS
+Align sky lines?  If yes then for the first object spectrum you are asked
+to mark one or more sky lines to use for alignment.  Then these lines will
+be found in all spectra and an average zeropoint shift computed and applied
+to the dispersion solution to align these lines.  Note that this assumes
+the sky lines are seen in all fibers.
+.LE
+skysubtract = yes
+.LS
+Subtract sky from the object spectra?  If yes the sky spectra are combined
+and subtracted from the object spectra as defined by the object and sky
+aperture/beam parameters.
+.LE
+skyedit = yes
+.LS
+Overplot all the sky spectra and allow contaminated sky spectra to be
+deleted?
+.LE
+saveskys = yes
+.LS
+Save the combined sky spectrum?  If no then the sky spectrum will be
+deleted after sky subtraction is completed.
+.LE
+splot = no
+.LS
+Plot the final spectra with the task \fBsplot\fR?
+.LE
+redo = no
+.LS
+Redo operations previously done?  If no then previously processed spectra
+in the objects list will not be processed (unless they need to be updated).
+.LE
+update = yes
+.LS
+Update processing of previously processed spectra if aperture, flat
+field, or dispersion reference definitions are changed?
+.LE
+batch = no
+.LS
+Process spectra as a background or batch job provided there are no interactive
+options (\f(CWskyedit\fR and \f(CWsplot\fR) selected.
+.LE
+listonly = no
+.LS
+List processing steps but don't process?
+.LE
+
+params = "" (pset)
+.LS
+Name of parameter set containing additional processing parameters.  The
+default is parameter set \fBparams\fR.  The parameter set may be examined
+and modified in the usual ways (typically with "epar params" or ":e params"
+from the parameter editor).  Note that using a different parameter file
+is not allowed.  The parameters are described below.
+.LE
+
+.ce
+-- PACKAGE PARAMETERS
+
+Package parameters are those which generally apply to all task in the
+package.  This is also true of \fBdoargus\fR.
+
+dispaxis = 2
+.LS
+Default dispersion axis.  The dispersion axis is 1 for dispersion
+running along image lines and 2 for dispersion running along image
+columns.  If the image header parameter DISPAXIS is defined it has
+precedence over this parameter.  The default value defers to the
+package parameter of the same name.
+.LE
+observatory = "observatory"
+.LS
+Observatory at which the spectra were obtained if not specified in the
+image header by the keyword OBSERVAT.  For Argus data the image headers
+identify the observatory as "kpno" so this parameter is not used.
+For data from other observatories this parameter may be used
+as describe in \fBobservatory\fR.
+.LE
+interp = "poly5" (nearest|linear|poly3|poly5|spline3|sinc)
+.LS
+Spectrum interpolation type used when spectra are resampled.  The choices are:
+
+.V1
+	nearest - nearest neighbor
+	 linear - linear
+	  poly3 - 3rd order polynomial
+	  poly5 - 5th order polynomial
+	spline3 - cubic spline
+	   sinc - sinc function
+.V2
+.LE
+database = "database"
+.LS
+Database (directory) used for storing aperture and dispersion information.
+.LE
+verbose = no
+.LS
+Print verbose information available with various tasks.
+.LE
+logfile = "logfile", plotfile = ""
+.LS
+Text and plot log files.  If a filename is not specified then no log is
+kept.  The plot file contains IRAF graphics metacode which may be examined
+in various ways such as with \fBgkimosaic\fR.
+.LE
+records = ""
+.LS
+Dummy parameter to be ignored.
+.LE
+version = "ARGUS: ..."
+.LS
+Version of the package.
+.LE
+
+.ce
+PARAMS PARAMETERS
+
+The following parameters are part of the \fBparams\fR parameter set and
+define various algorithm parameters for \fBdoargus\fR.
+
+.ce
+--  GENERAL PARAMETERS --
+
+line = INDEF, nsum = 10
+.LS
+The dispersion line (line or column perpendicular to the dispersion
+axis) and number of adjacent lines (half before and half after unless
+at the end of the image) used in finding, recentering, resizing,
+editing, and tracing operations.  A line of INDEF selects the middle of the
+image along the dispersion axis.
+.LE
+order = "decreasing" (apfind)
+.LS
+When assigning aperture identifications order the spectra "increasing"
+or "decreasing" with increasing pixel position (left-to-right or
+right-to-left in a cross-section plot of the image).
+.LE
+extras = no (apsum)
+.LS
+Include extra information in the output spectra?  When cleaning or using
+variance weighting the cleaned and weighted spectra are recorded in the
+first 2D plane of a 3D image, the raw, simple sum spectra are recorded in
+the second plane, and the estimated sigmas are recorded in the third plane.
+.LE
+
+.ce
+-- DEFAULT APERTURE LIMITS --
+
+lower = -3., upper = 3. (apdefault)
+.LS
+Default lower and upper aperture limits relative to the aperture center.
+These limits are used when the apertures are first found and may be
+resized automatically or interactively.
+.LE
+
+.ce
+-- AUTOMATIC APERTURE RESIZING PARAMETERS --
+
+ylevel = 0.05 (apresize)
+.LS
+Data level at which to set aperture limits during automatic resizing.
+It is a fraction of the peak relative to a local background.
+.LE
+
+.ce
+-- TRACE PARAMETERS --
+
+t_step = 10 (aptrace)
+.LS
+Step along the dispersion axis between determination of the spectrum
+positions.  Note the \f(CWnsum\fR parameter is also used to enhance the
+signal-to-noise at each step.
+.LE
+t_function = "spline3", t_order = 3 (aptrace)
+.LS
+Default trace fitting function and order.  The fitting function types are
+"chebyshev" polynomial, "legendre" polynomial, "spline1" linear spline, and
+"spline3" cubic spline.  The order refers to the number of
+terms in the polynomial functions or the number of spline pieces in the spline
+functions.
+.LE
+t_niterate = 1, t_low = 3., t_high = 3. (aptrace)
+.LS
+Default number of rejection iterations and rejection sigma thresholds.
+.LE
+
+.ce
+-- SCATTERED LIGHT PARAMETERS --
+
+buffer = 1. (apscatter)
+.LS
+Buffer distance from the aperture edges to be excluded in selecting the
+scattered light pixels to be used.
+.LE
+apscat1 = "" (apscatter)
+.LS
+Fitting parameters across the dispersion.  This references an additional
+set of parameters for the ICFIT package.  The default is the "apscat1"
+parameter set.
+.LE
+apscat2 = "" (apscatter)
+.LS
+Fitting parameters along the dispersion.  This references an additional
+set of parameters for the ICFIT package.  The default is the "apscat2"
+parameter set.
+.LE
+
+.ce
+-- APERTURE EXTRACTION PARAMETERS --
+
+weights = "none" (apsum)
+.LS
+Type of extraction weighting.  Note that if the \f(CWclean\fR parameter is
+set then the weights used are "variance" regardless of the weights
+specified by this parameter.  The choices are:
+
+"none"
+.LS
+The pixels are summed without weights except for partial pixels at the
+ends.
+.LE
+"variance"
+.LS
+The extraction is weighted by the variance based on the data values
+and a poisson/ccd model using the \f(CWgain\fR and \f(CWreadnoise\fR
+parameters.
+.LE
+.LE
+pfit = "fit1d" (apsum) (fit1d|fit2d)
+.LS
+Profile fitting algorithm for cleaning and variance weighted extractions.
+The default is generally appropriate for Argus data but users
+may try the other algorithm.  See \fBapprofiles\fR for further information.
+.LE
+lsigma = 3., usigma = 3. (apsum)
+.LS
+Lower and upper rejection thresholds, given as a number of times the
+estimated sigma of a pixel, for cleaning.
+.LE
+nsubaps = 1 (apsum)
+.LS
+During extraction it is possible to equally divide the apertures into
+this number of subapertures.
+.LE
+
+.ce
+-- FLAT FIELD FUNCTION FITTING PARAMETERS --
+
+f_interactive = yes (fit1d)
+.LS
+Fit the composite one dimensional flat field spectrum interactively?
+This is used if \f(CWfitflat\fR is set and a two dimensional flat field
+spectrum is specified.
+.LE
+f_function = "spline3", f_order = 10 (fit1d)
+.LS
+Function and order used to fit the composite one dimensional flat field
+spectrum.  The functions are "legendre", "chebyshev", "spline1", and
+"spline3".  The spline functions are linear and cubic splines with the
+order specifying the number of pieces.
+.LE
+
+.ce
+-- ARC DISPERSION FUNCTION PARAMETERS --
+
+threshold = 10. (autoidentify/identify/reidentify)
+.LS
+In order for a feature center to be determined the range of pixel intensities
+around the feature must exceed this threshold.
+.LE
+coordlist = "linelists$ctiohenear.dat" (autoidentify/identify)
+.LS
+Arc line list consisting of an ordered list of wavelengths.
+Some standard line lists are available in the directory "linelists$".
+.LE
+match = -3. (autoidentify/identify)
+.LS
+The maximum difference for a match between the dispersion function prediction
+value and a wavelength in the coordinate list.
+.LE
+fwidth = 4. (autoidentify/identify)
+.LS
+Approximate full base width (in pixels) of arc lines.
+.LE
+cradius = 10. (reidentify)
+.LS
+Radius from previous position to reidentify arc line.
+.LE
+i_function = "chebyshev", i_order = 3 (autoidentify/identify)
+.LS
+The default function and order to be fit to the arc wavelengths as a
+function of the pixel coordinate.  The functions choices are "chebyshev",
+"legendre", "spline1", or "spline3".
+.LE
+i_niterate = 2, i_low = 3.0, i_high = 3.0 (autoidentify/identify)
+.LS
+Number of rejection iterations and sigma thresholds for rejecting arc
+lines from the dispersion function fits.
+.LE
+refit = yes (reidentify)
+.LS
+Refit the dispersion function?  If yes and there is more than 1 line
+and a dispersion function was defined in the arc reference then a new
+dispersion function of the same type as in the reference image is fit
+using the new pixel positions.  Otherwise only a zero point shift is
+determined for the revised fitted coordinates without changing the
+form of the dispersion function.
+.LE
+addfeatures = no (reidentify)
+.LS
+Add new features from a line list during each reidentification?
+This option can be used to compensate for lost features from the
+reference solution.  Care should be exercised that misidentified features
+are not introduced.
+.LE
+
+.ce
+-- AUTOMATIC ARC ASSIGNMENT PARAMETERS --
+
+select = "interp" (refspectra)
+.LS
+Selection method for assigning wavelength calibration spectra.
+Note that an arc assignment table may be used to override the selection
+method and explicitly assign arc spectra to object spectra.
+The automatic selection methods are:
+
+average
+.LS
+Average two reference spectra without regard to any sort parameter.
+If only one reference spectrum is specified then it is assigned with a
+warning.  If more than two reference spectra are specified then only the
+first two are used and a warning is given.
+This option is used to assign two reference spectra, with equal weights,
+independent of any sorting parameter.
+.LE
+following
+.LS
+Select the nearest following spectrum in the reference list based on the
+sorting parameter.  If there is no following spectrum use the nearest preceding
+spectrum.
+.LE
+interp
+.LS
+Interpolate between the preceding and following spectra in the reference
+list based on the sorting parameter.  If there is no preceding and following
+spectrum use the nearest spectrum.  The interpolation is weighted by the
+relative distances of the sorting parameter.
+.LE
+match
+.LS
+Match each input spectrum with the reference spectrum list in order.
+This overrides the reference aperture check.
+.LE
+nearest
+.LS
+Select the nearest spectrum in the reference list based on the sorting
+parameter.
+.LE
+preceding
+.LS
+Select the nearest preceding spectrum in the reference list based on the
+sorting parameter.  If there is no preceding spectrum use the nearest following
+spectrum.
+.LE
+.LE
+sort = "jd", group = "ljd" (refspectra)
+.LS
+Image header keywords to be used as the sorting parameter for selection
+based on order and to group spectra.
+A null string, "", or the word "none" may be use to disable the sorting
+or grouping parameters.
+The sorting parameter
+must be numeric but otherwise may be anything.  The grouping parameter
+may be a string or number and must simply be the same for all spectra within
+the same group (say a single night).
+Common sorting parameters are times or positions.
+In \fBdoargus\fR the Julian date (JD) and the local Julian day number (LJD)
+at the middle of the exposure are automatically computed from the universal
+time at the beginning of the exposure and the exposure time.  Also the
+parameter UTMIDDLE is computed.
+.LE
+time = no, timewrap = 17. (refspectra)
+.LS
+Is the sorting parameter a 24 hour time?  If so then the time origin
+for the sorting is specified by the timewrap parameter.  This time
+should precede the first observation and follow the last observation
+in a 24 hour cycle.
+.LE
+
+.ce
+-- DISPERSION  CORRECTION PARAMETERS --
+
+linearize = yes (dispcor)
+.LS
+Interpolate the spectra to a linear dispersion sampling?  If yes the
+spectra will be interpolated to a linear or log linear sampling
+If no the nonlinear dispersion function(s) from the dispersion function
+database are assigned to the input image world coordinate system
+and the spectral data are not interpolated.
+.LE
+log = no (dispcor)
+.LS
+Use linear logarithmic wavelength coordinates?  Linear logarithmic
+wavelength coordinates have wavelength intervals which are constant
+in the logarithm of the wavelength.
+.LE
+flux = yes (dispcor)
+.LS
+Conserve the total flux during interpolation?  If \f(CWno\fR the output
+spectrum is interpolated from the input spectrum at each output
+wavelength coordinate.  If \f(CWyes\fR the input spectrum is integrated
+over the extent of each output pixel.  This is slower than
+simple interpolation.
+.LE
+
+.ce
+-- SKY SUBTRACTION PARAMETERS --
+
+combine = "average" (scombine) (average|median)
+.LS
+Option for combining sky pixels at the same dispersion coordinate after any
+rejection operation.  The options are to compute the  "average" or "median"
+of the pixels.  The median uses the average of the two central
+values when the number of pixels is even.
+.LE
+reject = "none" (scombine) (none|minmax|avsigclip)
+.LS
+Type of rejection operation performed on the pixels which overlap at each
+dispersion coordinate.  The algorithms are discussed in the
+help for \fBscombine\fR.  The rejection choices are:
+
+.V1
+      none - No rejection
+    minmax - Reject the low and high pixels
+ avsigclip - Reject pixels using an averaged sigma clipping algorithm
+.V2
+
+.LE
+scale = "none" (none|mode|median|mean)
+.LS
+Multiplicative scaling to be applied to each spectrum.  The choices are none
+or scale by the mode, median, or mean.  This should not be necessary if the
+flat field and throughput corrections have been properly made. 
+.LE
+
+.ce
+ENVIRONMENT PARAMETERS
+.LP
+The environment parameter \fIimtype\fR is used to determine the extension
+of the images to be processed and created.  This allows use with any
+supported image extension.  For STF images the extension has to be exact;
+for example "d1h".
diff --git a/noao/imred/argus/params.par b/noao/imred/argus/params.par
new file mode 100644
index 00000000..72e01ace
--- /dev/null
+++ b/noao/imred/argus/params.par
@@ -0,0 +1,67 @@
+line,i,h,INDEF,,,"Default dispersion line"
+nsum,i,h,10,,,"Number of dispersion lines to sum or median"
+order,s,h,"decreasing","increasing|decreasing",,"Order of apertures"
+extras,b,h,no,,,"Extract sky, sigma, etc.?
+
+-- DEFAULT APERTURE LIMITS --"
+lower,r,h,-3.,,,"Lower aperture limit relative to center"
+upper,r,h,3.,,,"Upper aperture limit relative to center
+
+-- AUTOMATIC APERTURE RESIZING PARAMETERS --"
+ylevel,r,h,0.05,,,"Fraction of peak or intensity for resizing
+
+-- TRACE PARAMETERS --"
+t_step,i,h,10,,,"Tracing step"
+t_function,s,h,"spline3","chebyshev|legendre|spline1|spline3",,"Trace fitting function"
+t_order,i,h,2,,,"Trace fitting function order"
+t_niterate,i,h,1,0,,"Trace rejection iterations"
+t_low,r,h,3.,0.,,"Trace lower rejection sigma"
+t_high,r,h,3.,0.,,"Trace upper rejection sigma
+
+-- SCATTERED LIGHT PARAMETERS --"
+buffer,r,h,1.,0.,,Buffer distance from apertures
+apscat1,pset,h,"",,,Fitting parameters across the dispersion
+apscat2,pset,h,"",,,"Fitting parameters along the dispersion
+
+-- APERTURE EXTRACTION PARAMETERS --"
+weights,s,h,"none","none|variance",,Extraction weights (none|variance)
+pfit,s,h,"fit1d","fit1d|fit2d",,Profile fitting algorithm (fit1d|fit2d)
+lsigma,r,h,3.,,,Lower rejection threshold
+usigma,r,h,3.,,,Upper rejection threshold
+nsubaps,i,h,1,1,,"Number of subapertures
+
+-- FLAT FIELD FUNCTION FITTING PARAMETERS --"
+f_interactive,b,h,yes,,,"Fit flat field interactively?"
+f_function,s,h,"spline3",spline3|legendre|chebyshev|spline1,,"Fitting function"
+f_order,i,h,20,1,,"Fitting function order
+
+-- ARC DISPERSION FUNCTION PARAMETERS --"
+threshold,r,h,10.,0.,,"Minimum line contrast threshold"
+coordlist,f,h,linelists$idhenear.dat,,,"Line list"
+match,r,h,-3.,,,"Line list matching limit in Angstroms"
+fwidth,r,h,4.,,,"Arc line widths in pixels"
+cradius,r,h,10.,,,Centering radius in pixels
+i_function,s,h,"chebyshev","legendre|chebyshev|spline1|spline3",,"Coordinate function"
+i_order,i,h,3,1,,"Order of dispersion function"
+i_niterate,i,h,2,0,,"Rejection iterations"
+i_low,r,h,3.,0.,,"Lower rejection sigma"
+i_high,r,h,3.,0.,,"Upper rejection sigma"
+refit,b,h,yes,,,"Refit coordinate function when reidentifying?"
+addfeatures,b,h,no,,,"Add features when reidentifying?
+
+-- AUTOMATIC ARC ASSIGNMENT PARAMETERS --"
+select,s,h,"interp",,,"Selection method for reference spectra"
+sort,s,h,"jd",,,"Sort key"
+group,s,h,"ljd",,,"Group key"
+time,b,h,no,,,"Is sort key a time?"
+timewrap,r,h,17.,0.,24.,"Time wrap point for time sorting
+
+-- DISPERSION CORRECTION PARAMETERS --"
+linearize,b,h,yes,,,Linearize (interpolate) spectra?
+log,b,h,no,,,"Logarithmic wavelength scale?"
+flux,b,h,yes,,,"Conserve flux?
+
+-- SKY SUBTRACTION PARAMETERS --"
+combine,s,h,"average","average|median",,Type of combine operation
+reject,s,h,"avsigclip","none|minmax|avsigclip",,"Sky rejection option"
+scale,s,h,"none","none|mode|median|mean",,"Sky scaling option"