MDM Trouble Report for 2001 Feb 3

Telescope: 2.4m
Observer(s): Lepine, De Marco (Columbia)
Instrument: MkIII

Problem(s) Encountered:
There was no time lost formally, although the traking problems
(see below) might have cost us about 2 hours in lost efficiency.

Two problems were reported on the night report:

1) Before opening up it was noticed that the CCD temperature was
about -35C, despite the fact that after last night's problems
we have filled the dewar with extreme care. We refilled the dewar 
again using another can, which appeared to be fuller. We also tried
to use one of the cans from the 1.3 m. After a third attempt at
filling the dewar, we were satisfied that there was enough
nitrogen. We did not have any more problems during the night
and the CCD temperature remained at -100.

2) As it was reported for last night, the telescope tracking
    seened to be off: on acquiring a bright target, we resetted the 
    encoders, but on the next acquisition the star was not on the marked
    spot. Throughout the night newly acquired stars fell off the
    spot by 1 to 2 arcmin. Parhaps this is related to a minor problem
    noticed at the start of the night, while exposing the first standard.
    While hand-guiding the star drifted off the slit by about 
    30 arcsec in less than a second of time. This happened about 4 times 
    in succession, but did not happen again during the whole night.



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Submitted on 2001 Feb 4 [7:27:18]