MDM Observatory 2.4m Telescope Observing Report for 2010 Jun 21

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

Instrument: Nellie direct + Buckeye FW

Worked for 9 hours (all night)
Conditions were Photometric most of the night.
No equipment or software problems were encountered.

Seeing and Weather:
   Beg: Seeing 1.5 arcsec, Clear, Winds Moderate
   Mid: Seeing 1.1 arcsec, Clear, Winds Light & Variable
   End: Seeing 1.1 arcsec, Clear, Winds Light & Variable

Observing Summary:

Yet another nice clear night - though among the shortest!  Seeing
was pretty consistent, a little over 1 arcsecond.  

This was the first night using the Andor camera as an autoguider
for direct.  It produced nice round images and seemed to be
very reliable.  It does take somewhat more setup than the old 
guider, but once that's accomplished it's very efficient, 
especially when used in conjunction with the dial-a-guidestar 
feature of JSkyCalc24mGS.  The only issue is that it's hard to
get it to update much faster than 2 seconds or so with Maxim
DL, which means you have to be a little bit patient in 
centering things, but in practice you can usually do this
while the detector is reading, so there's almost no time lost. 
Maxim-DL makes it very easy to place the guide star 
consistently on the detector; with the known guide probe 
geometry, the target lands on the detector within a couple of
arcseconds of the desired position.

One minor problem -- Nellie is showing weak pattern noise 
identical to echelle (prior to its demise), but quite a bit
less intense.  The problem, whatever it is, seems to be 
common between the two detectors.  This is not much of an issue
for direct imaging. 

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Submitted on 2010 Jun 22 [5:40:26]