MDM Trouble Report for 2010 Dec 1

Telescope: 2.4m
Observer(s): Halpern, Agueros, Covey (Columbia, Cornell)
Instrument: Modspec

Problem(s) Encountered:
1.  Still having a lot of trouble keeping the coarse focus of the
guider camera in range, as has been reported in recent trouble
reports.   The guide stars are usually donuts that are too wide
to guide well.  We spent about an hour total in a half dozen attempts
to move and/or secure the motor into a focused position.
I could be wrong about this, but here are my opinions:
   On the one hand, the motor seems to slide freely under the 
influence of gravity.  So it stays relatively still when the
telescope is near zenith and the motor is horizontal, but not
when at the telescope is at large hour angle and the motor is tilted.
   On the other hand, I think that the tape that was attached
to the motor to try to secure it is counterproductive, because the
tape got stuck on the housing of the MIS.  This is not good, because
the motor is attached to the guide probe stage, which has to move around
relative to the MIS box.  I finally removed that piece of tape, and the
focus seems to be steadier.  Sorry if that piece of tape was important,
but it seemed to be preventing us from guiding.
    Someone should read the vernier during the day after a night in
which the guide star was in focus, which it seems to be now, so that
the reading can be recorded and saved.

2. It seemed for a while that the guider camera shutter was opening
and closing, even though the check-box to prevent this was checked.
However, at the end of the night I don't hear that shutter anymore.

3. In xmis, dx and dy motions of the guide probe started not to work.
I fixed this by reinitializing xmis.


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Submitted on 2010 Dec 2 [5:12:06]