Date: Wed, 02 Feb 2000 09:56:04 -0700
From: "s. a. snedden"
Subject: 2.5-m Obs Log (MJD 51526)
			Tuesday February  01, 2000
                   Apache Point Observatory SDSS 2.5m
                           Observing Log
                           (MJD 51576)
Observers:
		Steph Snedden (APO)
Visitors from Away:
		Connie Rockosi (UC)
		Jim Annis -- by phone
A pointing model with as many points as time permitted and collimation
were scheduled for tonight. We also planned to test data acquisition and
the tape pipeline by taking several long bias runs with the imager.
Weather prevented us from opening until about 12:30, so we were not able
to get as large a pointing model as desired. We did get one with about
50 points. It has not been analyzed yet. If I do this today, I will send
out an addendum to this log, otherwise, the next observing shift will
have to run TPOINT.
Partway into the pointing model, the rotator aborted at an angle of 9.14
deg. It did not take us too long to figure out that the rotator had
wrapped. We had noted during set-up that it was 180 degrees off and we
thought we had re-set it correctly. Not so. We tried using /rotWrap to
unwrap the rotator, but were ultimately unsuccessful. We finally
unwrapped it using the MCP Menu. We lost about 4 stars in the pointing
model due to this problem. The pointing model was finished well into
morning twilight.
We also ran several goDrift -biases to fill up some tapes that we could
run endNight on. Here is what should be on the tapes:
	RUN	APPROX # of FRAMES
	1096	15
	1097	175
	1098	510
	1099	300
	1100	40
Connie noted that id2 and id6 tapes still had a fair amount of space on
them when the others were full.
Jim Annis will run endNight, as he wants to check his code.
The new spectrograph LN2 fill system has been installed, and we spent
some time checking to see what telescope positions allow the supply
lines to reach the spectrographs. Both spectrographs can be reached at
the following positions:
	ALT	ROT
	5	0
	10	0
	20	0
	30	0
	35	10
We did not try any altitudes greater than this. A few leaks were found
in the system, and Connie worked on stopping them.
Problems: We noticed that when applying the alt brake at about 6
degrees, the brake would appear to engage, but the telescope would move
(without touching the wind baffle), then go out of closed loop. Also, at
6 degrees, while stowing the telescope for the night the following
happened: We would clear the brake, and the telescope would go out of
closed loop. Sometime, but not every time, it would start to fall. I
tried adjusting the counterweights, but did not notice any change in the
behavior. Finally, it fell to the 1 degree limit and we had to move it
back using the manual pendant (thanks for the help, Steve).
PRs will be filed.
Connie fixed the problem with last night's VME sd1 errors. She tracked
it down to a mis-seated mini-SCSI cable.
The wind baffle altitude motion interlock was bypassed during the manual
pendant move at the end of the night. The next shift of observers should
check to be sure it has been reset.
The spectro dewars were filled at 19:00 and again at 08:00. The imager
dewar was not replaced, as the only full dewars are up at the 3.5 meter,
and with the snow, it is a luge run from the 3.5-m to the 2.5m. I have
asked the day staff to bring a dewar down, and swap out the empty.
Weather:  Skies ranged from partly cloudy to clear. Humidity dropped
from 80% to 50%. Winds started out with gusts greater than 35 mph, and
this contributed to high particle levels (blowing snow). By midnight,
the wind and particle count started dropping so we could open by about
00:30.