<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <!--Converted with LaTeX2HTML 98.1p1 release (March 2nd, 1998) originally 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 Lippmann, Marek Rouchal, Martin Wilck and others --> <HTML> <HEAD> <TITLE>Extraction of Information</TITLE> <META NAME="description" CONTENT="Extraction of Information"> <META NAME="keywords" CONTENT="vol2"> <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="vol2.css"> <LINK REL="next" HREF="node27.html"> <LINK REL="previous" HREF="node19.html"> <LINK REL="up" HREF="node10.html"> <LINK REL="next" HREF="node25.html"> </HEAD> <BODY > <!--Navigation Panel--> <A NAME="tex2html1740" HREF="node25.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="icons.gif/next_motif.gif"></A> <A NAME="tex2html1737" HREF="node10.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="icons.gif/up_motif.gif"></A> <A NAME="tex2html1731" HREF="node23.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="icons.gif/previous_motif.gif"></A> <A NAME="tex2html1739" HREF="node1.html"> <IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="icons.gif/contents_motif.gif"></A> <BR> <B> Next:</B> <A NAME="tex2html1741" HREF="node25.html">Search Algorithms</A> <B> Up:</B> <A NAME="tex2html1738" HREF="node10.html">Computational Methods</A> <B> Previous:</B> <A NAME="tex2html1732" HREF="node23.html">Image Restoration</A> <BR> <BR> <!--End of Navigation Panel--> <H1><A NAME="SECTION00540000000000000000"> </A> <A NAME="ext-inf"> </A> <BR> Extraction of Information </H1> The previous sections have described the most frequently used computational techniques for image handling in optical astronomy. After the images have been calibrated and manipulated to give the best representation of the data the astronomical information has to be extracted. For frames which contain a large number of objects automatic methods are required to locate them. A set of parameters is then estimated for the individual objects (e.g. position, total intensity, or velocity) depending on type and observational technique. <P> <BR><HR> <!--Table of Child-Links--> <A NAME="CHILD_LINKS"> </A> <UL> <LI><A NAME="tex2html1742" HREF="node25.html">Search Algorithms</A> <LI><A NAME="tex2html1743" HREF="node26.html">Fitting of data</A> </UL> <!--End of Table of Child-Links--> <BR><HR> <ADDRESS> <I>Petra Nass</I> <BR><I>1999-06-15</I> </ADDRESS> </BODY> </HTML>
