MDM Trouble Report for 2014 Nov 18

Telescope: 2.4m
Observer(s): Dan Gifford (Michigan)
Instrument: OSMOS

Problem(s) Encountered:
After taking several science exposures, I noticed several  splotches  on the images 
which were rather large. During a previous run, Eric let me know that this can be due 
to moisture buildup, and using the nitrogen air tank for 5-15 minutes with a light 
amount of air flow can solve this issue. After attempting to do so, the problem got worse. 
I took multiple exposures over a 3 hr period and each looked increasingly  fogged out  with 
apparent dust spots as well. I closed at 4:30 as the problem didn't improve. 
There was low humidity in the air (~10%) and no wind throughout the night.

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Submitted on 2014 Nov 19 [4:29:41]