<!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>Instrumental data</TITLE> <META NAME="description" CONTENT="Instrumental 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="node553.html"> <LINK REL="previous" HREF="node551.html"> <LINK REL="up" HREF="node548.html"> <LINK REL="next" HREF="node553.html"> </HEAD> <BODY > <!--Navigation Panel--> <A NAME="tex2html8424" HREF="node553.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="icons.gif/next_motif.gif"></A> <A NAME="tex2html8421" HREF="node548.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="icons.gif/up_motif.gif"></A> <A NAME="tex2html8415" HREF="node551.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="icons.gif/previous_motif.gif"></A> <A NAME="tex2html8423" 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="tex2html8425" HREF="node553.html">Observational data</A> <B> Up:</B> <A NAME="tex2html8422" HREF="node548.html">Introduction</A> <B> Previous:</B> <A NAME="tex2html8416" HREF="node551.html">Telescope obstruction data</A> <BR> <BR> <!--End of Navigation Panel--> <H2><A NAME="SECTION003214000000000000000"> Instrumental data</A> </H2> Instrumentation tends to change from one run to the next. Filters get broken or lost, or deteriorate and are replaced. Detectors change with age, may be destroyed by careless users, or just die for unknown reasons. Instruments suffer ``improvements'' that change their characteristics. <P> Only data taken with a fixed configuration can be reduced together. Usually, this will include all of the data taken during a run; occasionally, an equipment change is necessary during a run. Data describing a fixed instrumental configuration can naturally be grouped together in a table describing each particular run, or part of a run. <P> <BR><HR> <ADDRESS> <I>Petra Nass</I> <BR><I>1999-06-15</I> </ADDRESS> </BODY> </HTML>
