MDM Observatory 1.3m Telescope Observing Report for 2021 Aug 24

Observer(s): Halpern
Institution(s): Columbia

Instrument: Templton

Worked for 8 hours (all night)
Conditions were Non-Photometric most of the night.
Problems were encountered, see the separate trouble report for details.

Seeing and Weather:
   Beg: Seeing 1.7 arcsec, Patchy Clouds, Winds Light & Variable
   Mid: Seeing 1.7 arcsec, Clear, Winds Light & Variable
   End: Seeing 1.5 arcsec, Clear, Winds Light & Variable

Observing Summary:

The first couple of hours were lost to threatening clouds.
Then I spent a couple of hours testing the collimation.
Finally, a 5.5 hour time series on a CV target.

Today the secondary spider translation was found to be loose and
was tightened  Tonight I did a full-sky test of the stability
by looking at out-of-focus images at different telescope positions.
It seems acceptable and stable. In-focus images appear better
than in recent years. It's still necessary to tweak the primary
mirror to get better centering, but I believe the difficult part
of the collimation is done.  (And so is this observing run).
Thanks to Eric, Tony, and Justin for their hard work on this.

The N-S dither disappeared since Eric loosened the preload.

The CCD temperature is -79 C, which I believe is ~15 degrees
warmer than normal.

The guider fine focus appears not to be working, although 
the images are close enough to focus for good guiding.

I was going to get a final pair of out-of-focus images at
zenith, but the CCD controller failed again.  You can see
a final out-of-focus image (#501) at the position of the 
last target on the ds9 display.

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Submitted on 2021 Aug 25 [5:19:52]