MDM Observatory 2.4m Telescope Observer's Report for 2001 Feb 04

Observer(s): S. Lepine
Institution(s): Columbia

Instrument: Mk III spectrograph

Worked for 11 hours (all night)
Conditions were Photometric most of the night.
Problems were encountered, see the summary for details.

Seeing and Weather:
   Beg: Clear, Winds Calm
   Mid: Clear, Winds Calm
   End: Clear, Winds Calm

Observing Summary:

The sky was generally clear, and seeing was good. Our 
observations were however affected by the relative brightness
of the sky due to moonlight. Especially since many of our 
targets were in the 4-7 hour range in RA, relatively close
to the current location of the moon.


The following problems were encoutered:

1) At the start of the night, it was noticed a feature in the 
biases: a drop by 5-10 counts into a block of 300-400 consecutive
CCD lines. The location of the block would change from bias to
bias. Nothing unusual was noticed in the flats. This had
negligible effect on our observations.

2) At about 1:00AM, it was noticed that the dome slit was 
misaligned with the telescope by 10 degrees, occulting about
20-30% of the field of view. It is not known when or how the
misaligment occured. Dome encoders were reset accordingly.

3) As mentionned in previous night report. We had problems
acquiring our targets on the guider camera. The RA/DEC encoders
were reset on a bright standard at the start of the night. Pointing
on the guide camera (slit mode) would then be off by 1-2 arcmin
on subsequent acquisitions.

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Submitted on 2001 Feb 5 [7:20:23]