VISTA README

INTRODUCTION

This comprises the release of xvista, version 5.1; xvista has been previously distributed under the name vista or lickvista. The last release before this one was version 4.7. Xvista is an image processing program designed to be used primarily with astronomical data. It contains routines for reading, displaying, basic image processing, and specialized tasks for the analysis of astronomical imaging and spectroscopic data. Xvista was originally developed by graduate students and staff at the University of California, Santa Cruz. Modifications and additions continue to be supplied by several different people. The current version is maintained and distributed by Jon Holtzman at the New Mexico State University. The code is written primarily in Fortran 77, although there are also some C routines.

CONTENTS OF THIS DISTRIBUTION

This distribution contains all of the xvista source code, and also ancillary packages. The plotting routines of xvista use the LickMongo plotting package, which was also developed at the University of California, Santa Cruz, although it was based on the original Mongo package by John Tonry. The distribution also contains the source code for lynx, which is a text-based WWW browser which is used to display the xvista help files. Lynx was developed at the University of Kansas, and it is included here in an unmodified form as a convenience for xvista users; the version of lynx included herein will only be unpacked and compiled (automatically) if the main xvista Makefile finds that lynx does not already exist on your system. Finally, some of the routines from the DAOPHOT stellar photometry package, written by Peter Stetson at the Dominion Astrophysical Observatory, are included.

COPYRIGHT ISSUES

As a result of several packages being included , different portions of this distribution have different copyright protections. For the main xvista source code, see the files xvista/source/COPYHEADER and xvista/source/COPYING. For the LickMongo source code, see the files lickmongo/COPYRIGHT. For the lynx source code, see the files lynx2-8/COPYHEADER and lynx2-8/COPYING which will exist if the lynx code contained here is compiled.

WARRANTY and RELIABILITY

xvista is distributed without any type of warranty. See the file WARRANTY for additional information. Vista was an image processing program originally developed at Lick Observatory by Richard Stover and Tod Lauer. Since then, it has been significantly expanded with contributions from many different people, in particular several generations of graduate students at Lick. In recent years, it has incorporated code from various outside sources as well, most notably plotting and display code modified from source contributed by John Tonry, and an older version of DAOPHOT contributed by Peter Stetson; any comments or questions about these routines should be directed to the Vista distributors. Vista has been used extensively by many people and we feel that it is a reliable and useful package. However, VISTA is in no way guaranteed. The source code was contributed by several different people; we are indebted to all of them. All questions or comments about the code should be directed to the Vista distributors. None of the authors can be held responsible for any of the results obtained with Vista.

NEW FEATURES IN VERSION 5.0

xvista 5.0 has been significantly reorganized from previous versions. It has been modified so it can be compiled and run on a Linux platform using the f2c and gcc compilers. In addition, the help files have been extensively modified and written in LaTeX, with on-line help available through a WWW browser on HTML pages generated from the manual by the program latex2html. Numerous modifications and revisions have been made to various pieces of the code to provide additional functionality and to fix existing bugs. These changes are too numerous to describe individually. One new feature of interest in the ability to display very large images automatically by binning or sampling the raw data.

NEW FEATURES IN VERSION 5.1

Version 5.1 incorporates more changes and bug fixes. In particular, the handling of MASKs has been completely redone to allow for dynamic allocation of MASKs and consequently, MASKs of different sizes. In addition, I have enhanced RD to be able to read (inefficiently) FITS files which use image extensions (e.g. the NOAO MOSAIC cameras). Several of the spectroscopy routines for line identification and wavelength calibration have been enhanced to include graphical output.

BUGS, ETC

We hope that this version of VISTA is as bug-free as possible, but realistically understand that there may still be some problems. We are happy to hear from you about any problems you might have either with installation or with execution of the program. If there are any major problems, we will issue patches or replacement subroutines in the near future. Minor revisions will be incorporated into future releases. We encourage VISTA users to become VISTA programmers, as we feel that the accesibility of VISTA programming is among VISTA's strongest points. Accordingly, we have begun to prepare a programmers guide to VISTA. This has not yet been completed, but the current version can be found in PostScript form, as well as in TeX format, in the directory xvista/doc with the name progguide.ps and progguide.tex. Any comments on this document would be most appreciated. It is currently in a stage of development, so we do not guarantee any information in it.

OBTAINING XVISTA

You can obtain xvista from http://astro.nmsu.edu/~holtz/xvista

INSTALLATION

Installation should be extremely easy. Instructions are found in the file INSTALLATION.

DISCLAIMERS

NOTE ABOUT THE VISTA/DAOPHOT INTERFACE

After some discussion with Peter Stetson, the author of DAOPHOT, I wish to clarify some points/concerns about the version of DAOPHOT that has been installed within VISTA.

the version in VISTA was adapted from Stetson's 1987 version of the code. Subsequently, Peter has made many modifications, which have not been incorporated into the VISTA version.
some modifications to the DAOPHOT code were required to make the interface between DAOPHOT and VISTA, although effort was made to keep as much of the original code as possible.
many new features have been added to the code by Jon Holtzman. Generally, these features are turned on by changing the default options. Stetson is in no way responsible for these routines.

Because an older version of the code is being used and also because of the modifications that had to be made to provide for the VISTA interface, Stetson can NOT be held responsible for any results that come out of the VISTA/DAOPHOT program. From extensive use of the code, I feel that the routines are reliable, but this cannot be absolutely guaranteed. It is possible to use Stetson's up-to-date version of DAOPHOT by writing out your images from VISTA and then running the standalone version of DAOPHOT. On VMS systems, the data can be directly written in the Caltech data structures format which can be used with DAOPHOT. On UNIX systems, the data can be written in FITS format and translated to one of the DAOPHOT supported formats (IRAF or MIDAS) using IRAF, MIDAS or another translation program. A current version of DAOPHOT can be obtained by contacting Stetson directly. Any questions about the VISTA/DAOPHOT routines should be addressed to the VISTA distributors and not to Stetson. E-mail addresses for comments/questions/complaints are:
holtz@nmsu.edu
Publications using the VISTA/DAOPHOT routines should give credit to Peter (the standard reference is Stetson 1987, PASP 99, 191), but remember, he cannot be held responsible for the results.

NOTE ABOUT THE VISTA/MONGO INTERFACE

The current version of Vista does NOT depend on having a standalone version of MONGO to compile or run. The plotting routines which have been incorporated into Vista are based on routines which originated in the MONGO package of John Tonry, but which were modified extensively by Lick personnel. If anyone desires to have a standalone version of MONGO, they should contact Tonry directly (jt@antares.mit.edu).