MDM Observatory 2.4m Telescope Observer's Report for 2004 Feb 15

Observer(s): Matthew Walker
Institution(s): Michigan

Instrument: 8k

Worked for 12 hours (all night)
Conditions were Photometric most of the night.
Problems were encountered, see the separate trouble report for details.

Seeing and Weather:
   Beg: Seeing 1.5 arcsec, Clear, Winds Calm
   Mid: Seeing 1.1 arcsec, Clear, Winds Calm
   End: Seeing 1.1 arcsec, Clear, Winds Calm

Observing Summary:

Imaged fields in Andromeda, Leo, and Sextans.  Photometric conditions
with adequate seeing throughout the night, consistently ~1.1 arcsec.
Had two problems with telescope though:

1. As has happened on two previous nights, the telescope 
got jostled out of position during exposures early in the night.  I previously
attributed this to wind, but since the wind has never been strong
(or even measurably above zero mph), this may in fact be due to something mechanical.

Every time this has happened, the telescope has been at an hour 
angle near -3:00.  The telescope experiences a series of pulsating 
jerks due eastward, as I can tell by viewing the guider.  

2. The tcs is losing track of the dome.  I noticed the dome
was partially occulting the telescope midway through
the night, and hope that my exposures were not affected--they don't appear
to be, but it is hard to tell near the edge of the chip.  When I 
noticed it, the dome was occulting the southwest portion of the FOV.
This had no effect on the guider camera, so if by chance the guider
camera is southwest of the detector (?), then I can be reasonably certain
that my images were not affected.



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Submitted on 2004 Feb 16 [7:11:56]