MDM Observatory 1.3m Telescope Observing Report for 2012 Sep 21

Observer(s): S. Lepine
Institution(s): AMNH

Instrument: Direct + 4K

Worked for 7 hours (most of the night)
Conditions were Non-Photometric most of the night.
Problems were encountered, see the separate trouble report for details.

Seeing and Weather:
   Clouds from 3am until .
   Beg: Clear, Winds Light & Variable
   Mid: Clear, Winds Light & Variable
   End: Patchy Clouds, Winds Light & Variable

Observing Summary:

Some patchy clouds at sunset which dissipated. Clear
conditions through midnight, after which patchy clouds came
back again, increasing in numbers. Stopped observing 
around 3am because of cloud cover.

Noticed again a slow but significant drift of the stars 
on the ccd image over the night. The same field was
observed from 7pm to 1am, with flawless guiding. However,
all stars were see drifting by about 20 pixels along Y axis, 
and over 60 pixels along X axis, between the first (7pm) and
last (1am) frames. There was a 30 pixels jump as the star
passed the meridian, with a sudden 10 pixel jump seen occurring
during an 5min exposure. Again, the guiding seemed to be
perfectly good.


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Submitted on 2012 Sep 22 [6:40:30]