MDM Trouble Report for 2013 Aug 31

Telescope: 1.3m
Observer(s): Halpern (Columbia)
Instrument: Nellie

Problem(s) Encountered:
I had persistent problems with condensation on the dewar window.  I purged with dry nitrogen twice, once during the day and once at night.  But it would come back an hour later.  This seems surprising as the humitidy was only 71%.  The outside of the dewar feels dry.  The humidity is expected to decrease tomorrow night, so maybe that will help.  Note: it is necessary to push the bead up to the top to get enough nitrogen to clear the condensation.

Another disappointment is the recurrence of the N-S nodding.  It was intermittent while observing at declination +76, where most of tonight's observations were made.

On a positive note, the telescope pointed very well from the start, and the guiding is very good when it is not nodding.

------------------------------

Submitted on 2013 Sep 1 [5:48:37]