MDM Trouble Report for 2018 Jan 11

Telescope: 2.4m
Observer(s): Douglas (Columbia)
Instrument: OSMOS/R

Problem(s) Encountered:
Over the course of the night and during even minor slews, the telescope focus varied.
In a slew of only a few degrees, it changed by ~5 units. Over the course of an hour
or so following open cluster targets, it changed by ~20 units. This happened 
repeatedly over the night. Temperature changes may be responsible for some of 
the long term variation, but the change when I slewed is definitely something I 
don't recall encountering before. For example, when I slewed from a target to a 
telluric standard, focus went up by 5; when I went back to the target, focus 
dropped by 5. A slew of 30 deg at the end of the night changed the focus by 
almost 20 units. 

The dome also didn't want to go home again at the end of the night. It was at 
Az~270, and I couldn't get it to move either by switching Dome Mode=Home 
or saying Dome Target=Azimuth and trying to send it to 320. I was able to move 
it with the paddle, and happened to take my finger off the button around Az~300,
after which it trundled home happily. The dome was in a similar west-facing position
last night when it also wouldn't go home, so I wonder if there is something making 
it stick (physically or in software) over there. 

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Submitted on 2018 Jan 12 [6:35:13]