MDM Observatory 2.4m Telescope Observer's Report for 2004 Sep 15

Observer(s): Paust
Institution(s): Dartmouth

Instrument: Echelle

Worked for 8 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 1.8 arcsec, Clear, Winds Light & Variable
   Mid: Seeing 1.1 arcsec, Clear, Winds Light & Variable
   End: Seeing .8 arcsec, Clear, Winds Light & Variable

Observing Summary:

Started the night with the unhappy surprise that the mirror covers wouldn't open.  The north petal was hitting the center baffle and getting stuck.  I tried several open-close cycles at declinations ranging from 90 N to -5S without success.  I gave Bob a call and was able to solve the problem by slewing north and giving the baffle a few solid taps with the push broom.  Got it fixed soon enough to still get I flats.

There were a few tracking glitches like the ones that have been occurring.  They don't seem to depend on position on the sky and slewing and then moving back usually fixes the problem although you may have to do it more than once.  I did lose a 10 minute exposure to one of the glitches.

The seeing started out horrible, but around midnight started to improve.  My primary target was at an airmass of 1.6 at 1 am and I was getting better images than I did at an airmass of 1.1 a few hours earlier.

By morning twilight I was getting images around .8 arcsec in V for a 450s exposure.

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Submitted on 2004 Sep 16 [6:17:59]