Photometry in Crowded Fields

[Tass Mailing List <tass@mail.alembic.net>]

Date: Thu, 14 Feb 2008 15:41:41 -0400
From: Andrew Bennett <andrew.bennett@ns.sympatico.ca>
To: tass@tass-survey.org
Subject: Photometry in Crowded Fields

I have written up a review of TASS photometry (and incidentally
astrometry) that is intended to continue the "warts and all"
approach that Tom championed. It is on my website at
http://www3.ns.sympatico.ca/andrew.bennett/tass/errors.html

Executive Summary:

The standard TASS Pipeline has been subject to repeated tests against
alternative methods of analysis. In spite of claims to the contrary
(especially those by the present author,) no other method has provided
better photometry. The user is warned again that the accuracy of
magnitude measurement, determined by confusion errors, is a good
deal worse than the short term internal scatter of the measurements.
The astrometry of the Pipeline measurements could be improved by about
a factor of two if somebody thought this was worth the effort.

Andrew Bennett, Avondale Vineyard, Nova Scotia.