<!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>General Information</TITLE> <META NAME="description" CONTENT="General 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="node66.html"> <LINK REL="previous" HREF="node64.html"> <LINK REL="up" HREF="node64.html"> <LINK REL="next" HREF="node66.html"> </HEAD> <BODY > <!--Navigation Panel--> <A NAME="tex2html2248" HREF="node66.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="icons.gif/next_motif.gif"></A> <A NAME="tex2html2245" HREF="node64.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="icons.gif/up_motif.gif"></A> <A NAME="tex2html2239" HREF="node64.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="icons.gif/previous_motif.gif"></A> <A NAME="tex2html2247" 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="tex2html2249" HREF="node66.html">What Data Frames can</A> <B> Up:</B> <A NAME="tex2html2246" HREF="node64.html">Object Search and Classification</A> <B> Previous:</B> <A NAME="tex2html2240" HREF="node64.html">Object Search and Classification</A> <BR> <BR> <!--End of Navigation Panel--> <H1><A NAME="SECTION00710000000000000000"> General Information</A> </H1> INVENTORY has been originally designed as a medium speed and medium accuracy universal program for finding, classifying, and investigating astronomical objects on two-dimensional image frames in a way that is as automatic as possible. In a course of further development, both speed of execution and attainable precision have been improved, and the package differs from other related programs mainly by its tendency to minimise the amount of time spent by a user on interactive work at the terminal. Though it can be used for most of the relevant applications, <TT>INVENTORY</TT> is best suited for analysing numerous similar frames, like in cases of surveys or variable stars observations. It is also convenient for a first look preview of the material that will be analysed with more elaborate methods. It is not recommended for users who are not willing to give up the possibility of interactive control. A major requirement imposed on <TT>INVENTORY</TT> was that it should be able to classify detected objects into <I>stars</I>, <I>galaxies,</I> and <I>image defects</I>. <BLOCKQUOTE> <DIV ALIGN="CENTER"> <B>Note</DIV> <I>While it is possible to run <TT>INVENTORY</TT> for the first time without many preparations, achieving good results requires some experience. The program runs in an automatic mode when some parameters are set to proper values. Different applications may require different values for these parameters. Using <TT>INVENTORY</TT> with a new kind of material requires some preparation and trial runs are necessary for adjusting the parameters. The time spent on tuning up the program is well paid off when there is a sufficiently large number of objects and/or frames so that the use of other techniques would be much more time consuming. The tuning up may be difficult in a crowded field with many overlapping objects, or in a case where there are big bright galaxies. On the other hand the use of <TT>INVENTORY</TT> should be relatively easy when the investigated field is populated mainly by not too densely packed stars.</I></B></BLOCKQUOTE> <P> These photometric packages which aspire to high accuracy of results have to solve the problem of deblending of overlaping images. In its base mode <TT>INVENTORY</TT> does it in a fast but approximate way. A somewhat more accurate deblending of stellar objects using one-dimensional point spread function is now optional. Two dimensional point spread function fit, its extension to strongly undersampled images, and more precise deblending of galaxies are in preparation. <P> The program is functionally divided into three discrete steps. It will be possible to perform these steps using the commands: <TT>SEARCH/INV</TT>, <TT>ANALYSE/INV</TT>, and <TT>CLASSIFY/INV</TT>. The additional commands <TT>SHOW/INV</TT> and <TT>SET/INV</TT> serve for displaying and updating values of the <TT>INVENTORY</TT> keywords. <P> Before using <TT>INVENTORY</TT> commands it is necessary to give command <TT>SET/CONTEXT INVENT</TT>. It may be convenient to include this command into the <TT>login.prg</TT> file.<DL COMPACT> <DT> <BR> <DD>The (optional) <TT>SEARCH/INV</TT> command prepares a preliminary list of objects. The <TT>SEARCH/INV</TT> can be omitted once we have a list of objects with accurate positions in a MIDAS table format. <DT> <BR> <DD>The <TT>ANALYSE/INV</TT> command evaluates and updates an input list of objects. It can be used in a <TT>VERIFY</TT> or <TT>NOVERIFY</TT> mode. In <TT>VERIFY</TT> mode, the <TT>ANALYSE/INV</TT> command verifies the used table of objects. Some entries are deleted but usually a larger number of new ones are added. The objects positions are improved. In <TT>NOVERIFY</TT> mode this verification process is omitted. In both modes the <TT>ANALYSE/INV</TT> command calculates several image parameters, which can be used as final results and/or as input to the <TT>CLASSIFY/INV</TT> command. <DT> <BR> <DD>The <TT>CLASSIFY/INV</TT> command uses the output table produced by the <TT>ANALYSE/INV</TT> command for dividing the objects into <I>stars, galaxies</I> and <I>spurious objects</I>. It accepts only input of MIDAS table files that have been produced by <TT>ANALYSE/INV</TT>. </DL> <P> <HR> <!--Navigation Panel--> <A NAME="tex2html2248" HREF="node66.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="icons.gif/next_motif.gif"></A> <A NAME="tex2html2245" HREF="node64.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="icons.gif/up_motif.gif"></A> <A NAME="tex2html2239" HREF="node64.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="icons.gif/previous_motif.gif"></A> <A NAME="tex2html2247" 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="tex2html2249" HREF="node66.html">What Data Frames can</A> <B> Up:</B> <A NAME="tex2html2246" HREF="node64.html">Object Search and Classification</A> <B> Previous:</B> <A NAME="tex2html2240" HREF="node64.html">Object Search and Classification</A> <!--End of Navigation Panel--> <ADDRESS> <I>Petra Nass</I> <BR><I>1999-06-15</I> </ADDRESS> </BODY> </HTML>