DAOPHOT: A Stellar Photometry Package

Starting in VISTA Version 4, the package DAOPHOT, written by Peter Stetson (Dominion Astrophysical Observatory), has been included to facilitate image interaction and a common file storage system. Generally, the original DAOPHOT commands have been changed as little as possible. Consequently, many of the fancy features of VISTA cannot be interfaced with the DAOPHOT routines. For example, DAOPHOT images always have origin (1,1) while VISTA can handle arbitrary image limits. For the most part, however, the interface is straightforward to use. All of the DAOPHOT routines which require a file with image data in standalone DAOPHOT now require a buffer number with the image in memory. All of the photometry output data is stored in disk files exactly as DAOPHOT always stores it. See the DAOPHOT manual for all the details. Not all of the DAOPHOT routines are implemented.

We have found that interfacing DAOPHOT with VISTA is extremely convenient because several command line interfaces were created. In many routines, keywords have been implemented for the DAOPHOT commands that require keyboard input, facilitating running things in procedures and batch. In addition, a facility has been provided for providing hard wired default file names for use with the DAOPHOT routines. If the various photometry files (.COO, .AP, .MAG, .GRP, .NST, etc.) are previously specified with the DAOFILES command, the DAOPHOT routines will not prompt the user for entries, but will rather use the appropriate file as specified with the DAOFILES command. This is immensely useful for writing VISTA procedures to do whole chunks of the reduction process as painlessly as possible.

The version of DAOPHOT which is included in VISTA is an adaptation of Stetson's 1987 version of the code. Subsequently, Stetson has made modifications to the standard distribution of DAOPHOT which are NOT included in the VISTA package. In addition, some modification of the original DAOPHOT code was necessary to make it work inside of VISTA. Several new options were added as well by Jon Holtzman. Because of these facts, Stetson can NOT be help responsible for any results that come out of the VISTA/DAOPHOT routines. From extensive use of the code, we feel the routines are reliable, but this cannot be absolutely guaranteed. We are very grateful to Peter Stetson for allowing us to incorporate his code.

If you wish to use a Stetson's up-to-date version of DAOPHOT, contact him for the source code, and simply use VISTA to write out the data in some format which the standalone DAOPHOT can read.

Any questions about the VISTA/DAOPHOT routines should be addressed to the VISTA distributors and not to Stetson. Publications using the VISTA/DAOPHOT routines should give credit both to VISTA and to Stetson but remember, he cannot be help responsible for the results.

I leave the full description of all the DAOPHOT commands to the DAOPHOT manual. Here, I summarize the available DAOPHOT commands (HELP is available for these in a very limited way): OPTIONS, FIND, PHOTOMETRY, GROUP, PSF, PEAK, NSTAR, SUB* MONITOR, NOMONITOR, SORT, OFFSET, SELECT, APPEND, DAOSKY, and DUMP.