MDM Observatory 2.4m Telescope Observer's Report for 2004 Feb 28

Observer(s): John Thorstensen
Institution(s): Dartmouth

Instrument: echelle direct + 2in FW

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 1.3 arcsec, Clear, Winds Moderate
   Mid: Seeing 1.3 arcsec, Clear, Winds Moderate
   End: Seeing 0.9 arcsec, Cirrus, Winds Light & Variable

Observing Summary:

Pretty good night, iffy at sunset but cleared off perfectly 
(bright moon); seeing was inconsistent but mostly quite usable.
Some wind early on died down late and the seeing improved.  
Humidity was above 50% all night but never approached limit.

Ambient dome temperature often starts reading crazy values.  
The dewpoint is computed from this (plus the RH), so the dewpt
is apparently greater than the mirror temperature, which leads
to panicky messages being flashed on the mirror A/C control
monitor, and also to incorrect disabling of mirror cooling 
during these episodes.  So it is worth a trouble rpt I think.

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Submitted on 2004 Feb 29 [7:02:36]