[Aavso-photometry] variable comp star in field of TT Ari?

[Jim Roe]

Arne Henden wrote:
> My reading of your data is that 20071030 was significantly
> different for all of your stars, not just the target.  That always
> worries me.  What are your exposure times - are you running
> into saturation with the 10th magnitude star (it is the brightest
> of the set)?  What is different about 20071030 - worse seeing,
> clouds, what?  Why are 471 and 473 brighter than normal
> on that date?  I'd also be suspicious of your flatfielding on that
> night.

The worst night was 20071031 due to scattered clouds and I had to throw 
out a lot of images in the time series.  The only thing I can think of 
right now is that the 20071030 images were taken later in the evening, 
hence higher in the sky.  I don't think the 10.8 star was saturated, the 
exposures were only 10 seconds but I will check when I get back from 
Boston. :-) (Leaving for the airport in 5 hours - got to get *some* sleep.)

Jim Roe [ROE]