Re: FITS tables

[<aah@nofs.navy.mil>]

Jure asked about whether the raw starlists should use
magnitude or total counts.
  The reason for using magnitudes rather than total integrated
counts is twofold:  (a) magnitude is not really a derived
quantity, but rather just a different representation of the
same value and is the 'unit' that everyone uses; (b) many of
the profile fitting programs output magnitude rather than
integrated counts.
  Aperture size is usually given in radius, but diameter is
also OK as long as you clearly indicate which is used.  I'd
also put in where the sky annulus was taken.
  I'd also include the name and version of the program creating
the star list.  Since the FITS table has a standard FITS header,
you have room for 36 lines in the header, so other fields can
be added from the original image fits header, comments, etc.
The main point is to keep the table itself simple and condensed.
Arne