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This webpage describes the flags used in the CFHTLS
photometric catalogues.
The flag column has a value of 0 if there were
no problems with the object, and greater than 0
if there were one or more problems with the object.
Anything with a flag>0 is unlikely to have a reliable
photometric redshift.
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0: good
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1: object is a point source (probably not a galaxy) which may or may
not be a problem depending on who you are. This is determined
by the half-light radius of the object.
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2: object is near enough a bright star (or other high background area
of the image) that its photometry is probably compromised.
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4: The object is probably spurious. These ``objects'' are caused
by correlated noise produced by in the stacking process
of the original CCD frames. They are identified by having large
half-light radii, while having faint magnitudes.
These codes can be summed: a code of 3 means the object is a star
in a overly bright bit of sky.
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