MDM Observatory 1.3m Telescope Observing Report for 2011 Jan 23

Observer(s): Jackie Faherty
Institution(s): American Museum of Natural History

Instrument: MKIII

Worked for 8 hours (all night)
Conditions were Non-Photometric most of the night.
Problems were encountered, see the separate trouble report for details.

Seeing and Weather:
   Clouds all night.
   Beg: Seeing 1 arcsec, Patchy Clouds, Winds Light & Variable
   Mid: Seeing 1.5 arcsec, Patchy Clouds, Winds Light & Variable
   End: Seeing 1 arcsec, Clear, Winds Light & Variable

Observing Summary:

I once again had to battle with a constantly warming detector.  
I woke up and the temperature had risen nearly 80 degrees to +3.
I filled the dewar but I was not able to get it to cool lower than ~-75
I started taking an exposure then filling the dewar to try to maintain
a temperature of ~-70. 

At ~11pm clouds moved in and I closed the dome as the 4m folks declared
that the clouds were thretening.  I re-opened at ~12:30am.

After re-opening I continued to fill the dewar then take an exposure
but tonight I was losing the cooling battle.  It did not hold a low
temperature for more than a few minutes.  

I filled the dewar for the last time at ~4:30am.  The nitrogen tank must be
very low.

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Submitted on 2011 Jan 24 [6:22:24]