On Sat, 3 May 2008 08:23:36 -0700 (PDT), Anthony Ayiomamitis
wrote:

I contacted a couple of individuals a priori surrounding this transit
and I was told that it is not possible in the slightest given the dim
magnitude of the parent star, the transit depth and my small aperture.

Nice work. FWIW, I calculate that with the ST2K and your aperture, you
should be able to record about 10,000 e- with a 45-second exposure,
which is sufficient for a S/N of several hundred. 10 mmag precision with
differential photometry is quite possible at that S/N. I'm not sure why
you were advised otherwise, but clearly your experience and theory are
in good agreement.

As long as your other planned observations involve stars not a lot
dimmer than this one, and are slow enough to allow reasonably long
exposures (as in this case), I'd say your prospects for successful
transit recordings are excellent.

The biggest problem I have with mmag photometry comes from local
transparency events- tiny clouds or contrails that are too faint to even
see visually can pass through the field and play havoc with short
exposure differential photometry. Around here (and I suspect near Athens
as well) that's more of a problem during the summer, so if you see
unexpectedly noisy data, suspect that. If your target is in a rich
enough field to support it, using multiple references helps (both Maxim
and AIP can do this).
_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com