MDM Observatory 2.4m Telescope Observing Report for 2018 Dec 08

Observer(s): Ryan Chornock
Institution(s): Ohio University

Instrument: OSMOS/B

Worked for 13 hours (all night)
Conditions were Photometric most of the night.
No equipment or software problems were encountered.

Seeing and Weather:
   Beg: Seeing 1.5 arcsec, Clear, Winds Calm
   Mid: Seeing 1.25 arcsec, Clear, Winds Light & Variable
   End: Seeing 1.75 arcsec, Clear, Winds Moderate

Observing Summary:

It was humid for the entire previous day.  Condensation had formed on the 4K dewar window by the afternoon, but I flushed it with dry N2 and it was fine afterwards.
The humidity spiked up above 90% around 5PM, so I was worried about how it was going to go after the temperature dropped at night. However, the dew point also plummeted after sunset. I was able to open by 6PM and worked the rest of the night without incident.
It was clear and dark all night long.  Seeing got worse towards morning when the winds kicked up.

The guider stage froze once and I had to power cycle the MIS controller during the night.  Minimal time loss.

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Submitted on 2018 Dec 9 [7:35:05]