Re: GSC 748-1618

[Michael Koppelman <lolife@bitstream.net>]

Here is a comparison of the comp star mags I used (Vty) and the mags 
for the same stars from tass (Vts):

Star          Vts    Vty    Vdif   Its    V-Its  B-Vty
GSC 748-2518  10.48  10.51  -0.03   9.06   1.41   0.96
GSC 748-1474  10.88  10.96  -0.08   9.66   1.21   0.97
GSC 748-2263  12.21  11.86   0.35  11.75   0.46   1.03
      Average  11.19  11.11   0.08

Vts   = V tass average
Vty   = V tycho-2
Vdif  = difference between tass and tycho
Its   = I tass average
V-Its = V-I tass average
B-Vty = B-V tycho-2

I could redo my photometry with the tass V mags. I don't suspect it 
will change the overall picture by more than 0.1m. Do you think that is 
what I should do?

It is my intention to get my transformation coefficients (with my new 
camera) and try to get some accurate VRI photometry on the comp stars. 
I'm also going to start to work on either the R or I band on the 
variable star.

Michael Koppelman