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Diffstat (limited to 'noao/imred/generic/doc')
| -rw-r--r-- | noao/imred/generic/doc/Spelldict | 51 | ||||
| -rw-r--r-- | noao/imred/generic/doc/background.hlp | 82 | ||||
| -rw-r--r-- | noao/imred/generic/doc/darksub.hlp | 60 | ||||
| -rw-r--r-- | noao/imred/generic/doc/flat1d.hlp | 157 | ||||
| -rw-r--r-- | noao/imred/generic/doc/flatten.hlp | 42 | ||||
| -rw-r--r-- | noao/imred/generic/doc/normalize.hlp | 45 | ||||
| -rw-r--r-- | noao/imred/generic/doc/normflat.hlp | 54 |
7 files changed, 491 insertions, 0 deletions
diff --git a/noao/imred/generic/doc/Spelldict b/noao/imred/generic/doc/Spelldict new file mode 100644 index 00000000..bb9573fb --- /dev/null +++ b/noao/imred/generic/doc/Spelldict @@ -0,0 +1,51 @@ +Chebyshev +INDEF +IRAF +Oct84 +RMS +Sep84 +biasimage +biassub +ccd +chebyshev +chimage.section +chimages +chimages.section +chimages.transpose +colbckgrnd +colflat +darkimage +darksub +datatype +dcbias +dcbias.bias +dcbias.trim +div +elp +expdark +expimage +flatfield +fliplines +frame1 +frame2 +frame3 +images.imcopy +imarith +imcopy +imlinefit +imred.keeplog +imred.logfile +imstatistics +imtranspose +legendre +linebckgrnd +lineflat +min +minflat +ndhelp +ngrow +normflat +pixtype +spline3 +trim.section + diff --git a/noao/imred/generic/doc/background.hlp b/noao/imred/generic/doc/background.hlp new file mode 100644 index 00000000..7fa1fdd6 --- /dev/null +++ b/noao/imred/generic/doc/background.hlp @@ -0,0 +1,82 @@ +.help background Jul85 noao.imred.generic +.ih +NAME +background -- Fit and subtract a line or column background +.ih +USAGE +background input output +.ih +PARAMETERS +.ls input +Images to be background subtracted. The images may contain image sections. +.le +.ls output +Output images to be created and modified. The number of output images must +match the number of input images. +.le +.ls axis = 1 +Axis along which to fit the background and subtract. Axis 1 fits and +subtracts the background along the lines and axis 2 fits and subtracts +the background along the columns. +.le +.ls interactive = yes +Set the fitting parameters interactively? +.le +.ls sample = "*" +Lines or columns to be used in the background fits. The default "*" selects +all lines or columns. +.le +.ls naverage = 1 +Number of sample points to combined to create a fitting point. +A positive value specifies an average and a negative value specifies +a median. +.le +.ls function = spline3 +Function to be fit to the image lines or columns. The functions are +"legendre" (legendre polynomial), "chebyshev" (chebyshev polynomial), +"spline1" (linear spline), and "spline3" (cubic spline). The functions +may be abbreviated. +.le +.ls order = 1 +The order of the polynomials or the number of spline pieces. +.le +.ls low_reject = 0., high_reject = 0. +Low and high rejection limits in units of the residual sigma. +.le +.ls niterate = 1 +Number of rejection iterations. +.le +.ls grow = 1. +When a pixel is rejected, pixels within this distance of the rejected pixel +are also rejected. +.le +.ls graphics = "stdgraph" +Graphics device for interactive graphics output. +.le +.ls cursor = "" +Graphics cursor input +.le +.ih +DESCRIPTION +For each line or column in the input images a function is fit to the columns +or lines specified by the sample parameter. This function is then subtracted +from the entire line or column to create an output line or column. +The function fitting parameters may be set interactively. +This task is a script using \fBfit1d\fR. For more discussion about +the parameters see the help text for \fBicfit\fR and \fBfit1d\fR. +.ih +EXAMPLES +A spectrum of an object runs down the center of a 500 x 500 image. To +subtract a constant background using columns 10 to 100 and 410 to 500: + + cl> background image image sample="10:100,410:500" + +To subtract a quadratic background from the columns of an image in which +the spectrum lies between lines 50 and 70: + + cl> background image image axis=2 sample="1:40,80:120" o=3 + +.ih +SEE ALSO +fit1d, icfit +.endhelp diff --git a/noao/imred/generic/doc/darksub.hlp b/noao/imred/generic/doc/darksub.hlp new file mode 100644 index 00000000..c6349e03 --- /dev/null +++ b/noao/imred/generic/doc/darksub.hlp @@ -0,0 +1,60 @@ +.help darksub Apr86 noao.imred.generic +.ih +NAME +darksub -- Scale and subtract a dark count image +.ih +USAGE +darksub input output darkimage +.ih +PARAMETERS +.ls input +List of input images from which to subtract the dark count image. +.le +.ls output +List of output dark count subtracted images. The output images may +be the same as the input images. The input and output image lists should +contain the same number of images. +.le +.ls darkimage +Dark count image to be scaled and subtracted from the input images. +.le +.ls exposure = "" +Header parameter name from which to obtain the exposure times. +.le +.ls pixtype = "1" +The pixel datatype of the dark subtracted images. The default ("1") +is the pixel datatype of the original image. The other choices are +"short", "integer", "long", "real", and "double". +.le +.ls verbose = yes +Print log of operations performed. +.le +.ih +DESCRIPTION +The dark count image is scaled by the ratio of the input image exposure to the +dark count image exposure and subtracted from each of the input images. +The exposures are obtained from the image headers under the specified +name. The output images may have the same names as the input images. +A temporary image is used for the scaled dark count image and the original +image is not modified. The pixel datatype of the output images is +specified by the parameter \fIpixtype\fR. The default ("1") uses the +datatype of the input image. A log of the operations performed may be +printed on the standard output when the verbose options is specified. + +Note that this task can be used to subtract any type of image from a set +of images in which the subtracted image must be scaled to a given exposure. +.ih +EXAMPLES +To subtract the dark count image 'dark' from obs1, obs2, and obs3: + +.nf + cl> darksub obs1,obs2 obs1,obs2 dark exp="exposure" + Tue 18:50:56 08-Apr-86 + obs1 = obs1 - 5.0049997336067 * dark + Tue 18:51:05 08-Apr-86 + obs2 = obs2 - 5.009999733075 * dark +.fi +.ih +SEE ALSO +imarith +.endhelp diff --git a/noao/imred/generic/doc/flat1d.hlp b/noao/imred/generic/doc/flat1d.hlp new file mode 100644 index 00000000..0f855828 --- /dev/null +++ b/noao/imred/generic/doc/flat1d.hlp @@ -0,0 +1,157 @@ +.help flat1d Mar93 noao.imred.generic +.ih +NAME +flat1d -- Make flat fields by fitting a 1D function to the image +.ih +USAGE +flat1d input output +.ih +PARAMETERS +.ls input +Calibration images to be used to make the flat fields. The images may +contain image sections. Only the region covered by the section will be +modified in the output image. +.le +.ls output +Flat field images to be created or modified. The number of output images +must match the number of input images. If an output image does not exist +it is first created and initialized to unit response. +.le +.ls axis = 1 +Axis along which the one dimensional fitting is done. Axis 1 corresponds +to fitting the image lines and axis 2 corresponds to fitting the columns. +.le +.ls interactive = yes +Set the fitting parameters interactively? +.le +.ls sample = "*" +Lines or columns to be used in the fits. +.le +.ls naverage = 1 +Number of sample points to combined to create a fitting point. +A positive value specifies an average and a negative value specifies +a median. +.le +.ls function = spline3 +Function to be fit to the image lines or columns. The functions are +"legendre" (legendre polynomial), "chebyshev" (chebyshev polynomial), +"spline1" (linear spline), and "spline3" (cubic spline). The functions +may be abbreviated. +.le +.ls order = 1 +The order of the polynomials or the number of spline pieces. +.le +.ls low_reject = 2.5, high_reject = 2.5 +Low and high rejection limits in units of the residual sigma. +.le +.ls niterate = 1 +Number of rejection iterations. +.le +.ls grow = 1. +When a pixel is rejected, pixels within this distance of the rejected pixel +are also rejected. +.le +.ls minflat = 0. +When the fitted value is less than the value of this parameter the flat +field value is set to unity. +.le +.ls graphics = "stdgraph" +Graphics device for interactive graphics output. +.le +.ls cursor = "" +Graphics cursor input +.le +.ih +DESCRIPTION +Flat fields are created containing only the small scale variations in the +calibration images. The large scale variations in the images are modeled +by fitting a function to each image line or column with deviant pixel rejection. +The flat field values are obtained by taking the ratio of the image values +to the function fit. However, if the fitted value is less than the +parameter \fIminflat\fR the flat field value is set to unity. + +The function fitting parameters may be set interactively when the interactive +flag is set using the interactive curve fitting package \fBicfit\fR. +The cursor mode commands for this package are described in a separate +help entry under "icfit". For two dimensional images the user is +prompted for the sample line or column or a blank-separated range to be +averaged and graphed. +Note that the lines or columns are relative the input image section; for +example line 1 is the first line of the image section and not the first +line of the image. Any number of lines or columns may be examined. +When satisfied with the fit parameters the user +responds with a carriage return to the line or column prompt. +The function is then fit to all the lines or columns and the flat field +ratios are determined. + +If the output image does not exist initially it is created with the same +size as the input image \fIwithout\fR an image section and initialized +to unit response. Subsequently the flat field data modifies the pixel +values in the output image. Input image sections may be used to restrict +the region in which the flat field response is determined leaving the +rest of the output image unmodified. This ability is particularly useful +when dealing with multi-aperture data. + +This task is very similar to \fBfit1d\fR with the addition of the +parameter \fIminflat\fR and the deletion of the parameter \fItype\fR +which is always "ratio". +.ih +EXAMPLES +1. Create a flat field from the calibration image "quartz" with the +spectrum running along the lines. Exclude the first and last columns, +use a spline fit of 25 pieces (a width of 32 pixels over 800 columns), +and set grow to 4 pixels. + +.nf + cl> flat1d quartz flat order=25 sample="2:799" grow=4 \ + >>> interactive=no + + or + + cl> flat1d quartz[2:799,*] flat order=25 grow=4 inter- +.fi + +The fitting parameters may be set interactively in which case the fitting +parameters need not be specified. The command would be + +.nf + cl> flat1d quartz flat + quartz: Fit column = 1 10 + quartz: Fit column = +.fi + +The user selects sample columns to be fit interactively with the interactive +curve fitting package. When satisfied with the fit parameters +respond with a carriage return to the prompt. The function is then fit to +all the columns and the flat field ratios are determined. + +2. As an example for multi-slit spectra the locations of the slits are +determined and a file containing the image sections is created. +Since there must be the same number of output images another file +containing the output images is also created. For +example the files might contain + +.nf + File quartzs File flats + _______________ __________ + quartz[23:40,*] flat + quartz[55:61,*] flat + quartz[73:84,*] flat +.fi + +A flat field for the slits is then obtained with the command + + cl> flat1d @quartzs flats axis=2 +.ih +REVISIONS +.ls FLAT1D V2.10.3 +The image header keyword "CCDMEAN = 1." is now added or updated. +.le +.ih +BUGS +The creation of multi-slit files and the need for an equal number of +repeated output files is annoying. It will be worked on in the future. +.ih +SEE ALSO +fit1d, icfit +.endhelp diff --git a/noao/imred/generic/doc/flatten.hlp b/noao/imred/generic/doc/flatten.hlp new file mode 100644 index 00000000..0e35f647 --- /dev/null +++ b/noao/imred/generic/doc/flatten.hlp @@ -0,0 +1,42 @@ +.help flatten Sep84 noao.imred.generic +.ih +NAME +flatten -- Flatten images by dividing by a flat field +.ih +USAGE +flatten images flatfield +.ih +PARAMETERS +.ls images +Images to be flattened. +.le +.ls flatfield +Flat field image to be divided into the images. +.le +.ls minflat = INDEF +All flat field pixels less than or equal to this value are replaced by +unit response. If INDEF all the flat field pixels are used. +.le +.ls pixtype = "real" +The pixel datatype of the flattened image. The null string ("") defaults +the pixel datatype to that of the original image before flattening. +The other choices are "short", "integer", "long", and "real". +.le +.ih +DESCRIPTION +Each of the \fIimages\fR is flatten by dividing by the \fIflatfield\fR +flat field image. The flattened images replace the original images. +The pixel datatype of the flattened images is specified by the +\fIpixtype\fR. The null string ("") leaves the datatype of the images +unchanged. Low values in the flat field may be replaced by unit response +by specifying a \fIminflat\fR value. All pixels in the flat field less +than or equal to \fIminflat\fR are given unit response. +.ih +EXAMPLES +To flatten a set of two dimensional images excluding pixels below +.2 in the flat field: + +.nf + cl> flatten frame* flat minflat=0.2 +.fi +.endhelp diff --git a/noao/imred/generic/doc/normalize.hlp b/noao/imred/generic/doc/normalize.hlp new file mode 100644 index 00000000..f5fb80f7 --- /dev/null +++ b/noao/imred/generic/doc/normalize.hlp @@ -0,0 +1,45 @@ +.help normalize Sep84 noao.imred.generic +.ih +NAME +normalize -- Normalize images +.ih +USAGE +normalize images +.ih +PARAMETERS +.ls images +Images to be normalized. +.le +.ls norm = INDEF +Normalization factor to be used if not INDEF. If INDEF the normalization +factor is determined by sampling the images. +.le +.ls sample_section = "[]" +Section of the image to be sampled in determining the image mean. +.le +.ls lower = INDEF +Lower limit of pixel values for calculating the normalization. +INDEF corresponds to the minimum possible pixel value. +.le +.ls upper = INDEF +Upper limit of pixel values for calculating the normalization. +INDEF corresponds to the maximum possible pixel value. +.le +.ih +DESCRIPTION +Each of the images is normalized. The normalization is specified by the +parameter \fInorm\fR. If the value of \fInorm\fR is INDEF then a normalization +is determined by sampling the image. The normalization is then the mean +of the pixels in the sample section with values in the range \fIlower\fR +to \fIupper\fR. The default sample section selects all pixels in the image. +The normalized images are of datatype "real" and replace the original images. +.ih +EXAMPLES +To normalize a set of two dimensional images excluding deviant pixels below +1000 and above 5000 and subsampling every fifth pixel in each dimension: + + cl> normalize frame* sample=[*:5,*:5] low=1000 up=5000 +.ih +SEE ALSO +imstatistics, normflat +.endhelp diff --git a/noao/imred/generic/doc/normflat.hlp b/noao/imred/generic/doc/normflat.hlp new file mode 100644 index 00000000..3020d296 --- /dev/null +++ b/noao/imred/generic/doc/normflat.hlp @@ -0,0 +1,54 @@ +.help normflat Sep84 noao.imred.generic +.ih +NAME +normflat -- Create a flat field by normalizing a calibration image +.ih +USAGE +normflat image flatfield +.ih +PARAMETERS +.ls image +Calibration image to be used. +.le +.ls flatfield +Flat field to be created. +.le +.ls norm = INDEF +Normalization factor to be used if not INDEF. If INDEF the normalization +factor is automatically determined. +.le +.ls minflat = INDEF +Minimum data value to be used in determining the normalization and in +creating the flat field. Values less than or equal to this value are +replaced with a flat field value of 1. +.le +.ls sample_section = "[]" +Section of the image to be sampled in determining the normalization if +norm = INDEF. +.le +.ih +DESCRIPTION +A flat field is created from a calibration image by normalizing the calibration +image. The normalization is specified with the parameter \fInorm\fR. If the +value of \fInorm\fR is INDEF then the normalization is determined by sampling +the pixels in the sample section with values greater than \fIminflat\fR. +This task differs from the task \fBnormalize\fR in that data values less +than or equal to \fIminflat\fR are replaced with unity in the normalized +flat field. +.ih +EXAMPLES +To create a flat field from a calibration image "quartz" using pixels +above 1000 and selecting the normalization to be 3500: + + cl> normflat quartz flat norm=3500 minflat=1000 + +To determine a normalization from the pixels above 1000 and sampling +every fifth pixel in each dimension: + +.nf + cl> normflat quartz flat minflat=1000 sample=[*:5,*:5] +.fi +.ih +SEE ALSO +normalize +.endhelp |