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diff --git a/src/slalib/sun67.htx/node189.html b/src/slalib/sun67.htx/node189.html new file mode 100644 index 0000000..a19516f --- /dev/null +++ b/src/slalib/sun67.htx/node189.html @@ -0,0 +1,160 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> +<!--Converted with LaTeX2HTML 97.1 (release) (July 13th, 1997) + by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds +* revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan +* with significant contributions from: + Jens Lippman, Marek Rouchal, Martin Wilck and others --> +<HTML> +<HEAD> +<TITLE>SLA_UNPCD - Remove Radial Distortion</TITLE> +<META NAME="description" CONTENT="SLA_UNPCD - Remove Radial Distortion"> +<META NAME="keywords" CONTENT="sun67"> +<META NAME="resource-type" CONTENT="document"> +<META NAME="distribution" CONTENT="global"> +<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso_8859_1"> +<LINK REL="STYLESHEET" HREF="sun67.css"> +<LINK REL="next" HREF="node190.html"> +<LINK REL="previous" HREF="node188.html"> +<LINK REL="up" HREF="node13.html"> +<LINK REL="next" HREF="node190.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html2316" HREF="node190.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html2314" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html2308" HREF="node188.html"> +<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="previous_motif.gif"></A> <A HREF="sun67.html#stardoccontents"><IMG ALIGN="BOTTOM" BORDER="0" + SRC="contents_motif.gif"></A> +<BR> +<B> Next:</B> <A NAME="tex2html2317" HREF="node190.html">SLA_V2TP - Direction Cosines to Tangent Plane</A> +<BR> +<B>Up:</B> <A NAME="tex2html2315" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html2309" HREF="node188.html">SLA_UE2PV - Pos/Vel from Universal Elements</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION0004176000000000000000">SLA_UNPCD - Remove Radial Distortion</A> +<A NAME="xref_SLA_UNPCD"> </A><A NAME="SLA_UNPCD"> </A> +</H2> + <DL> +<DT><STRONG>ACTION:</STRONG> +<DD>Remove pincushion/barrel distortion from a distorted +<IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img20.gif" + ALT="$[\,x,y\,]$"> to give tangent-plane <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img20.gif" + ALT="$[\,x,y\,]$">.<P> <DT><STRONG>CALL:</STRONG> +<DD><TT>CALL sla_UNPCD (DISCO,X,Y)</TT> +<P> </DL> +<P> <DL> +<DT><STRONG>GIVEN:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DISCO</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>pincushion/barrel distortion coefficient</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>X,Y</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>distorted <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img20.gif" + ALT="$[\,x,y\,]$"></TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>RETURNED:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>X,Y</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>tangent-plane <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img20.gif" + ALT="$[\,x,y\,]$"></TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>NOTES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>The distortion is of the form <IMG WIDTH="103" HEIGHT="31" ALIGN="MIDDLE" BORDER="0" + SRC="img128.gif" + ALT="$\rho = r (1 + c r^{2})$">, where <I>r</I> is +the radial distance from the tangent point, <I>c</I> is the DISCO +argument, and <IMG WIDTH="11" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img129.gif" + ALT="$\rho$"> is the radial distance in the presence of + the distortion. + <DT>2. +<DD>For <I>pincushion</I> distortion, C is +ve; for + <I>barrel</I> distortion, C is -ve. + <DT>3. +<DD>For X,Y in units of one projection radius (in the case of + a photographic plate, the focal length), the following + DISCO values apply: +<P> <BR> +<BR> +<BR> +<P> <TABLE CELLPADDING=3 BORDER="1"> +<TR VALIGN="TOP"><TD ALIGN="LEFT" NOWRAP>Geometry</TD> +<TD ALIGN="CENTER" NOWRAP>DISCO</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT" NOWRAP>astrograph</TD> +<TD ALIGN="CENTER" NOWRAP>0.0</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT" NOWRAP>Schmidt</TD> +<TD ALIGN="CENTER" NOWRAP>-0.3333</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT" NOWRAP>AAT PF doublet</TD> +<TD ALIGN="CENTER" NOWRAP>+147.069</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT" NOWRAP>AAT PF triplet</TD> +<TD ALIGN="CENTER" NOWRAP>+178.585</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT" NOWRAP>AAT f/8</TD> +<TD ALIGN="CENTER" NOWRAP>+21.20</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT" NOWRAP>JKT f/8</TD> +<TD ALIGN="CENTER" NOWRAP>+14.6</TD> +</TR> +</TABLE> +<P> <BR> +<BR> +<BR> +<P> <DT>4. +<DD>The present routine is an approximate inverse to the + companion routine sla_PCD, obtained from two iterations + of Newton's method. The mismatch between the sla_PCD + and sla_UNPCD is negligible for astrometric applications; + to reach 1 milliarcsec at the edge of the AAT triplet or + Schmidt field would require field diameters of <IMG WIDTH="25" HEIGHT="13" ALIGN="BOTTOM" BORDER="0" + SRC="img232.gif" + ALT="$2^{\circ} + \hspace{-0.37em}.\hspace{0.02em}4$"> and <IMG WIDTH="26" HEIGHT="13" ALIGN="BOTTOM" BORDER="0" + SRC="img233.gif" + ALT="$42^{\circ}$"> respectively. + </DL></DL> +<BR> <HR> +<A NAME="tex2html2316" HREF="node190.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html2314" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html2308" HREF="node188.html"> +<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="previous_motif.gif"></A> <A HREF="sun67.html#stardoccontents"><IMG ALIGN="BOTTOM" BORDER="0" + SRC="contents_motif.gif"></A> +<BR> +<B> Next:</B> <A NAME="tex2html2317" HREF="node190.html">SLA_V2TP - Direction Cosines to Tangent Plane</A> +<BR> +<B>Up:</B> <A NAME="tex2html2315" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html2309" HREF="node188.html">SLA_UE2PV - Pos/Vel from Universal Elements</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<ADDRESS> +<I>SLALIB --- Positional Astronomy Library<BR>Starlink User Note 67<BR>P. T. Wallace<BR>12 October 1999<BR>E-mail:ptw@star.rl.ac.uk</I> +</ADDRESS> +</BODY> +</HTML> |