[vsnet-chat 1265] Re: H/T chart vs. VT mags...

[bas@lowell.Lowell.Edu (Brian Skiff)]

>    I have heard the ICQ has recommended (if I understand corrently from
> indirect information) VT rather than V.  I hope this will not lead to further
> inconsistencies between variable star and comet observers.

     When Dan Green published the ICQ article about this early in 1998, I
found it rather astonishing.  The problem to me was that for many years he
had recommended (quite reasonably) that observers use only standard V
magnitudes from reliable sources.  But suddenly now he was saying to _ignore_
these sources and to use the uncorrected VT instead!  This can't help but
introduce systematic problems in the collected dataset.  Since for fainter
stars one still has standard V, and upcoming catalogues will show standard V
magnitudes for general surveys of faint stars, this seemed to me to be a
short-sighted change of systems.  Soon enough (five years?) we will have
reliable magnitudes for all stars in the sky to faint limits (at least to
the limits of the GSC, perhaps even A1.0), and the raw Tycho-system data
will be forgotten.

\Brian

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