Date: Mon, 26 Apr 1999 05:15:27 -0600
From: long@apo.nmsu.edu (Dan Long)
Subject: 2.5m obslog 990425 ( MJD 51294 )
                          SUNDAY APRIL 25, 1999
                     APACHE POINT OBSERVATORY SDSS 2.5m
                              OBSERVING  LOG
   The weather cleared around 22:00, but clouds just to the north continued
to show radar echoes ( from snow flurries it turns out ), until nearly
01:00.
   As the imager was still on the telescope and we needed to switch to the
engineering camera, I decided to wait until I was sure we could get a good
clear hour on the telescope to make the switch.
   The imager came off with no problems.  Putting on the engineering camera
was another matter.  After not finding it on the cart in the shed, Russell
and I spent the better part of an hour and a half trying to get the
manipulator to work.  For starters, the breaker was off, when there is a
switch to turn it on and off in the control box.  Second, the light curtain
was also off at the breaker.  Third the lift would not operate from the
normal up and down switches.  Only the buttons on the wall inside the rack
area would move the lift.  Fourth and most exasperating, the air was turned
off to the manipulators.  It took us a very long time to determine that
this was the problem, and to find the valve.  I would certainly like to
know why things were left in such a state.  I saw no messages about there
being problems with the manipulators or the air system.  The hour and a
half we lost kept us from being able to do a pointing model.
   With the little time we had left once the engineering camera was on was
used to test some of Russell's new TCC code and the pointing model routine.
In exercising the telescope, we concluded that it worked as well as before
in terms of the new TCC and the current MCP.  Spectrograph installation is
due to begin tomorrow, so this may be the last night work for the next
couple days.
                                Dan