MDM Observatory 2.4m Telescope Observer's Report for 2002 Feb 11

Observer(s): Pinkney
Institution(s): Michigan

Instrument: Modular Spectacular

Worked for 10 hours (most of the night)
Conditions were Non-Photometric most of the night.
No equipment or software problems were encountered.

Seeing and Weather:
   Beg: Seeing 1.2 arcsec, Clear, Winds Moderate
   Mid: Seeing 1.0 arcsec, Clear, Winds Light & Variable
   End: Seeing 0.82 arcsec, Cirrus, Winds Light & Variable

Observing Summary:

Calcium triplet spectroscopy of nearby galaxies was performed.

I spent several hours trying to optimize the spectrograph's
focus.  (This cut into the first few hours of dark time, but
this is not disasterous since most of our objects are not
observable until midnight.  Also, I picked up twilight flats
in the morning.)  I achieved what appeared to be a minimum
FWHM in the 4-D space of PL1,PL2,TL1 and Coll, and yet this
value was only about 2.4 pix, whereas previous observer's
(including myself) achieve ~1.8 pix.  More to the point,
duplicating old setups did not give a FWHM < 2.4 pix. Duplicating
some old setups was seemingly impossible because the tightening
screws become completely loose before the desired values are 
reached.
Also, returning to the same settings I had earlier in the night
did not give the same FWHM readings.  So I maintain that 
the focusing system is a bit flakey (i.e. non-repeatable).

The wind was down and the temperature up compared to the last
few frigid nights making observing more enjoyable.  The seeing
improved to <1.0  in the latter half of the night.

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Submitted on 2002 Feb 12 [7:45:01]