MDM Observatory 2.4m Telescope Observer's Report for 2006 Nov 09

Observer(s): L. Watson
Institution(s): OSU

Instrument: CCDS and Retrocam

Worked for 7.5 hours (off and on through the night)
Conditions were Non-Photometric most of the night.
No equipment or software problems were encountered.

Seeing and Weather:
   High Humidity from 00:45 until 04:45.
   Beg: Seeing 1.2 arcsec, Clear, Winds Light & Variable
   Mid: Clear, Winds Calm
   End: Seeing 1.5 arcsec, Clear, Winds Calm

Observing Summary:

The humidity started rising early in the night (40% by 8pm).  By
12:45am, the humidity was up to 70% and rising.  The temperature 
outside was about 10C and the dew point was about 5C.  The 
primary mirror temperature was 12C and the dome dew point was 
7C.  I closed up because it looked like condensation was in the 
future.  These conditions stuck around (with on average a 5 
degree difference between the temperature and the dew point).  
The humidity would rise and fall, with the highest value 77%.  
I think I might have been too conservative, but I stayed closed.  
Around 4:45am though, the humidity dropped dramatically and has
continued dropping (it's down to 38% now).  The dew point and 
temperature of course became more widely separated and I 
decided to open up until sunrise.  It's amazing how much the 
humidity varied: from 77% to 38%!  Wow!  Also amazing is that
it was perfectly clear for this entire drama.

I think this is well known, so I won't call it a problem, but
the auto dome does get confused when you are observing near 
zenith.  It rotates around for a good while until it has 
convinced itself that it is in the correct position.  This 
happened three times tonight.  I'm sure the dome must obscure 
the telescope during this rotation.

When I wasn't closed, I observed three SDSS supernova, one
lens and a blazar for M. Bentz.

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Submitted on 2006 Nov 10 [7:08:05]