RE: orion tricolor

[aah@nofs.navy.mil]

Tim Hager wrote:
>     As an aside, this tri-color image might be useful for discovering new
>variables via the "red star" method.  I looked up the GSC plate data for
>one very red star in the tricolor and found it measured 13.5 and 15.5 on
>two plates taken many months apart.  A new Mira?
  Sure, just casual examination of such tricolors can find new red or
blue objects.  Another nice feature is finding obvious regions of extinction,
where you see an overabundance of red objects...these are not necessarily
intrinsically red like Miras.  Of course, software can find red or blue
objects a lot quicker, but the eye picks out patterns better.
Arne