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	Thu, 30 Mar 2006 16:39:09 PST
Date: Thu, 30 Mar 2006 16:39:09 -0800 (PST)
From: Tim Crawford <tcarchcape

About a year ago I began, what for me was, a very
frustrating search for information on ensemble
photometry.  I used both the NASA ADS search engine as
well as the AAVSO’s.  There were a number of papers
available regarding the topic of ensemble photometry
but few that presented “method” information in a way
that the seemed to be readily understandable by the
typical AAVSO CCD observer.  In addition, not that it
might not exist, I was unable to locate a single
document that explained or described the summing of
magnitudes into what I term a “Master Star” value;
although there were references to this approach being
used in some of the modules for IRAF software.

In any event I pulled together the various options
available for “solving” for an ensemble solution as
best I could determine them and have attempted to
explain them with the use of actual data in the form
of examples.

An MS word version and a PDF version can be found at
the following.  Be sure and choose “File Sharing” at
the top of the page then the “Download” option when
the “MyiDisk” folder appears:

http://homepage.mac.com/windwalker1/

To the Stars

Tim Crawford  CTX



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