Subject: 2.5m obslog 19990907 (MJD 51429)
Date: Wed,  8 Sep 1999 06:45:16 -0600 (MDT)
From: hayes@apo.nmsu.edu
			Tuesday September 07, 1999
		              (MJD 51429)
                   Apache Point Observatory SDSS 2.5m
                           Observing Log
Tonight's Observing Team:
                Francisco Castander (UC)
		Ellyne Kinney (APO)
                Jeffrey Hayes (APO)
                David Schegel (PU)
		Connie Rockosi (UC)  -- PIC
		Bill Boroski (FNAL)
                Bob Nichol (CMU)
We started the TPM log at about 19:00 MDT.  The all-sky camera, Bing started
and the DIMM was started at about 21:30.  Seeing started off reasonable at
about 1.3" but continued to deteriorate to 1.7" to 2" over the night.
We opened at about 20:00 MDT and worked on getting fiducials set, along with
the counterweights to their proper positions.  We needed to move the
counterweight on SP2 to its old location as we could not get the rotator to
balance quite right -- note, that we will have to move this again, if we put
the mosaic camera on, as there is not enough clearance for the imager and
the counterweight to co-exist.  By the telescope counerweights were set to
150V.  After getting the initial balance, etc., ready, we were on the sky
at 21:23 MDT.
We did a focus sequence on Alpha-Aql (which was found right-away, so our
initial pointing model was probably good enough to this accuracy.  We found
that, because of the cirrus moving over us quite quickly, the focus would
change dramatically, but we settled on a value of -2300 (in TCC units).
We were ready for a short (12 point) pointing model at 23:00.  The first model
we obtained using PTERRKLUDGE gave an RMS of over 5".  We decided to
repeat the 12 point model using DOPTERR.  This model gave an RMS=2.6" --
(fit to 8 terms) but with a comparatively large change from the last pointing
model that was done before the August spectroscopic run.  We decided to
load this new 12 point model and use it as the basis for a 34 point model.
We started up the 34 point model at 01:10 MDT.  The model went quite fast
except for the fact that we had to punch through quite a bit of cirrus --
enough to act as a reasonable ND filter.  (I.e. we had to hunt and peck
through holes in the clouds.)  We finished the 34 point model at 01:55 MDT --
the cirrus clearing out during that time.  On analysing this 34 point model,
we found that using 14 terms to fit that data, we could obtain an RMS of
2.28".  We deleted one (1) point from the initial dataset and obtained
an RMS = 1.84" using 14 terms.  We deemed this model reasonable and so
loaded it as the new pointing model.
We put the mosaic camera on the telescope starting at 02:15 and completed
it (including 2 MCP reboots and finding the ficucials again) by 03:15.  We
moved the weight on the rotator/SP2 back to the position it was in when we
opened.  The reboots were required for: 1) getting the MCP to respond after
we had finished the 34 point pointing model -- the MCP would not respond to
Menu commands after repeated "axis stop" commands from within the TCC; 2)
we lost the MCP after the mosaic camera was put on, and we were setting the
fiducials.  Note that the counterweight voltages were set to their maximae:
720, now that the imager is back on.
At 04:00 we set up on the equator/meridian (0,57.22), with the rotator at 90d
in mount co-ords.  We obtained a series of focus frames which Ellyne and Connie
have saved to disk.  This was while parked on the equator.  At 05:15 we did
a "scanStrip 86 -30 -strip N" (i.e. off equator scanning), and after
resetting the focus back to -1770, we obtained data.  Note that we had a
problem starting the TCC session from within the default version of "iop" as
the LatNode for the TCC is still set to tcctest, not tcc25m.  A new version
of the code must be made with this bug fixed.  We started the focus loop at
05:30.  We stopped collecting data at 05:55.
we did have a severe problem with the endNight script -- neither Connie
or I could figure out the problem, as we tried various fixes and still
no success.  Obviously a bug-fix for the programmers involved here.
Dewars:
We replenished the LN2 in: SP1 at 16:30
                         ; SP2 at 22:20
			 ; SP1 at 03:20
We called it a long but reasonably useful night at 07:00 MDT.
Jeffrey.