[vsnet-chat 7252] Re: [vsnet-obs 53846] Re: data format correction

[gvnn64 at libero.it]

> Likewise, as mentioned, use of USNO-A (or any astrometric catalog,
> including UCAC) for photometry is highly discouraged; the photometry
> is basically a placeholder so that field recognition can be accomplished.

Hi Arne,
I would like to know your opinion about this:

http://www.iac.es/galeria/mrk/comets/USNO_Landolt.htm

According the Author, the USNO-A2 is not so bad for "semi-accurate" (say, 0.1 to 0.2 magn. accuracy) photometry. What do you think?

Thanks,
Giovanni Sostero