On Tue, 13 Dec 2005, Tim Jenness wrote:
>> Now I don't now the details of how EXTRACTOR and the unnamed pipeline
>
> I think Brad was saying that EXTRACTOR uses an ellipse fitting of a contour.
It definitely doesn't do this, you'd need ESP for that method. SExtractor,
as Malcolm says, uses weighted moments of all the background-subtracted
data within the isophote (forgetting about any deblending) to determine an
ellipse. This is also what PISA does, which undoubtedly still shares code,
or at least methods, with the unnamed pipeline (same author).
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