<!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>Raw to Calibrated Data</TITLE> <META NAME="description" CONTENT="Raw to Calibrated Data"> <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="node19.html"> <LINK REL="previous" HREF="node11.html"> <LINK REL="up" HREF="node10.html"> <LINK REL="next" HREF="node16.html"> </HEAD> <BODY > <!--Navigation Panel--> <A NAME="tex2html1638" HREF="node16.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="icons.gif/next_motif.gif"></A> <A NAME="tex2html1635" HREF="node10.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="icons.gif/up_motif.gif"></A> <A NAME="tex2html1629" HREF="node14.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="icons.gif/previous_motif.gif"></A> <A NAME="tex2html1637" 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="tex2html1639" HREF="node16.html">Artifacts</A> <B> Up:</B> <A NAME="tex2html1636" HREF="node10.html">Computational Methods</A> <B> Previous:</B> <A NAME="tex2html1630" HREF="node14.html">Estimation</A> <BR> <BR> <!--End of Navigation Panel--> <H1><A NAME="SECTION00520000000000000000"> </A> <A NAME="raw-to-cal"> </A> <BR> Raw to Calibrated Data </H1> The actual transformation of raw detector data to clean maps in intensity scale depends strongly on both the imaging and detecting systems. However, three typical steps can be identified, namely: detection and removal artifacts in the data, correction for non-linear effects or relative variations in sensitivity of the detector system, and correction for geometric distortions in the imaging device. Although the order of the first two steps can often be interchanged the geometric correction must be performed last because it involves a rebinning of the data which assumes them to be intensities. <P> <BR><HR> <!--Table of Child-Links--> <A NAME="CHILD_LINKS"> </A> <UL> <LI><A NAME="tex2html1640" HREF="node16.html">Artifacts</A> <LI><A NAME="tex2html1641" HREF="node17.html">Response Calibration</A> <LI><A NAME="tex2html1642" HREF="node18.html">Geometric Corrections</A> </UL> <!--End of Table of Child-Links--> <BR><HR> <ADDRESS> <I>Petra Nass</I> <BR><I>1999-06-15</I> </ADDRESS> </BODY> </HTML>
