Date: Tue, 15 Sep 1998 03:37:48 -0600
From: long@apo.nmsu.edu (Dan Long)
Subject: 2.5m obslog 980914
                          MONDAY SEPTEMBER 14, 1998
                     APACHE POINT OBSERVATORY SDSS 2.5m
                              OBSERVING  LOG
   Enclosure was rolled off at about 18:30.  Work was done today tightening
the slack in the chain which drives the windscreen in altitude.  This was
apparently the cause of the oscillations noted earlier.  The gain has been
increased to 5 and performs well in following telescope motion.
   Pat Waddell and I got set up on Polaris shortly after 19:30.  We got a
couple hours of data in deteriorating weather conditions before having to
close at 21:30 due to clouds.  Clouds, high winds, and occasional light
rain persisted for the rest of the night.  Seeing was quite poor ( >2
arcsec ) with strong winds out of the East while we were open.
   In the time we were open, we found that the primary position of last
night did not yield the same symmetric images we obtained last night.  We
think this is due at least in part to the telescope/optics not having
reached thermal equilibrium.  Unfortunately as we were unable to reopen, we
could not test this hypothesis.
                                   Dan