Overview of the Photometric Pipeline: PSP and Frames

December 1996. Photo version: $Name: $

This document gives a quick view of the overall operation of the Photometric Pipeline. It should be the equivalent of a short talk, one in which the speaker mentions the structure of a complex problem and briefly touches on a number of issues. It will not describe exactly how the Pipeline operates --- for that, you should try looking at the documentation for specific routines or at the source code.

We have a number of technical papers on photo. These should probably be integrated with this document at some point.

This is a first draft, not a finished product. We intend to modify it as desired by readers (especially the JPG) who require more information on specific topics. Please send any comments or suggestions to Zeljko Ivezic, Robert Lupton, or Jill Knapp at Princeton. With your help, we can improve this document.

  • How to Find Things in Photo
  • The Postage Stamp Pipeline (`PSP')
  • The Frames Pipeline (`Frames')
  • Photo's Fundamental Datatypes
  • Saved Outputs Of Photo's Measure Objects
  • Miscellaneous Algorithms
  • Known Bugs
  • References
  • How to Find Things in Photo

    This document is not a precis of the photo code; if you want to find out exactly how things are done, you'll want to read the source.

    To run photo, you'll first have to acquire a standard SDSS environment, and install all products required to run astrotools (or photo if you don't want to build it yourself). You can then say setup photo and proceed to the next paragraph.

    The TCL top-level routines to run the PSP is in

        $PHOTO_DIR/etc/ps_pipeline.tcl
    
    you may want to use cvs to check out your own copy of photo. There's more code in $PHOTO_DIR/etc/ps_pipeline_procs.tcl and $PHOTO_DIR/etc/photo_procs.tcl.

    The frames pipeline routines are in the same place, but called frames_pipeline.tcl and frames_pipeline_procs.tcl

    The main routines are called run_ps_pipeline and run_frames_pipeline, and each expects one argument, the name of the file that gives the desired order of business, and the location of all files required to run the postage stamp or frames pipeline.

    If you are familiar with emacs' TAGS files, you can profitably say sdssmake tags in $PHOTO_DIR to make browsing the source easier; tags are built for both C and TCL symbols.