MDM Observatory 2.4m Telescope Observer's Report for 2001 Feb 03

Observer(s): Lepine, De Marco
Institution(s): Columbia

Instrument: MkIII

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

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

Observing Summary:

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.

------------------------------

Submitted on 2001 Feb 4 [7:24:48]