TASS data reduction

[Chris Albertson <chris@topdog.pas1.logicon.com>]

In a nutshell here is what I intend to do to process MkIII
images.  With no camera here all i've done is studied HELP
files and tried to learn script writing.  Here's the
plan:

1) extract stars list with DAOFIND.  Produces very rough
   photometry but good center locations even for blends.
   DAOFIND uses convolution with the PSF followed by 
   thresholding then centrioding to make an object list.

2) Search the list for the "top 5%" model stars.  These are
   not saturated, near other stars, or blends.

3) build a PSF model using the above 35 ~ 50 stars as input
   to the model builder.  This produces a PSF model that 
   can vary with (x,y) that is good only for the current
   frame.  (I do think the PSF varies in ra.  The VCO drifts
   and seeing can change.)

4) Determine intsrumental mag for each star in the list
   by fitting the local PSF at each star's x,y location.

The only new code I would need to write is #2.  I think
that is not so hard to do.  Just read in a list and out
put a subset of the lines based on some crieria.

Any dumb ideas here?

-- 

--Chris Albertson

  chris@topdog.logicon.com                Voice:  818-351-0089  X127
  Logicon RDA, Pasadena California          Fax:  818-351-0699