[vsnet-chat 1372] Re: comparison of GSPC and USNO-based V mags

[Taichi Kato <tkato>]

Re: comparison of GSPC and USNO-based V mags

(Re: vsnet-chat 1370)

>    The expected magnitudes are systematically roughly 0.2 mag brighter than
> GSPC V, ...

  Sorry, should read 'fainter'.

  I tried on stars south of -33 deg (as suggested by Dr. Skiff).  There is
a nearly 1 magnitude "dip" for stars of V mags between 10.5 and 13.5 (only
too useful range for visual observers!).  For this magnitude range, the
expected V mag tend to be brighter.  This is not the effect of the color
calibration, since the formula give better approximations to V mags outside
this magnitude region.

Regards,
Taichi Kato

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