[Aavso-photometry] [AAVSO-DIS] new comparison star database

[Michael Koppelman]

In the ideal world of high-quality sequences, it shouldn't matter  
which 11.2 star you used if they are both really 11.2. In the past  
our confidence was low that 11.2 really meant 11.2.

I know the AAVSO likes to know exactly which comp stars were used,  
which is why uniqueness is desired, but hopefully the high-quality  
sequences will make that somewhat academic.

Cheers,
M.
http://www.starhouseobservatory.com/




On Oct 25, 2007, at 7:32 AM, arne wrote:

> (1) Stars on a given chart with the same label.  This will
> happen due to two reasons: overlapping sequences (two variables
> on the same chart which might have had identical-magnitude
> stars in the two sequences), and revised photometry converging
> two close-magnitude stars.  For example, two stars on a chart
> might have had labels 113 and 111, and after photometry revision,
> they both become 112.  In the past, we solved this problem by
> indicating the offset direction from the target star, such
> as 112W or 112NE.  For now, I suggest that if two stars have
> the same label, use the star closest to the target if possible,
> and if there is a possibility of confusion, indicate in the
> comment field (not the compstar field) the offset direction.
> Then, let HQ know that there is a problem with this field
> (an email to vspcharts - att aavso.org will do), and we will remove
> one of the two stars (you might give us some guidance as to
> which should be removed).