Date: Mon, 17 May 1999 05:51:49 -0600 (MDT)
From: hayes@apo.nmsu.edu
Subject: 2.5 m obslog 990516 (MJD 51315)
			Sunday May 16, 1999
		Apache Point Observatory SDSS 2.5m
			     Observing Log
Observing Team:
		Jeffrey Hayes (APO)
		Ellyne Kinney (APO)
                Rob't Lupton (PU)
                Scott B (UC)
                Connie Rockosi (UC)
		David S. (PU)
Weather:  Clear with low dust.  Windy: ~20 mph steady and gusts
up to 32 mph.
Tonight was a repeat of Saturday night -- try and get spectra.  However
we did change to the new cartridge with plate 135.  In the change and the
fitting, everything went fine.  The counterweights were set to 340 each, and
the display for C 2 has been fixed.
We opened at roughly 10 pm MT as Larry Carey and Connie were performing some
tests on the secondary.  Larry also made some adjustments to the slithead
on the new cartridge -- again, that went well.
We started by slewing to a nearby FK5 star 243.56666,-3.69055, with the
following offset to account for the distance between the boresight and
fiber10  -0.119198,-0.098545.  We found the star and made some offset calibs
to center the star, the offset was -0.012,0.001.
We then went to the field center at 241.25,0.  There were no stars down any of
the fibers.  We made offsets ranging from .001 to .03 in all directions.
We found faint stars in fiber 1 and 3 but no stars in 10.  We then realized
that the coords we used were epoch 1998.5 and not 2000.0.  We found coords
for the FK5 star in 2000.0 243.70561,-3.59576.  We went back to the FK5 star.
We found what may have been a diffraction spike, but any offset we made
(.001 to .03 in four directions) only moved the light out the the fiber.
We also tried offsetting in two axes at once to try and move along the
diagonal, with no luck.
We tried pointing to several objects during the night with no luck.
The objects were:
NGC5921	230.4675, 5.0750    1998.5
M13	250.4225,36.4602    2000.0
Arcturus	213.9096,19.1850    2000.0
FK5	243.5667,-3.6906    1998.5
FK5	243.7056,-3.5958    2000.0
After the initial error with epoch in the beginning of the night
we made sure to tell the tcc which epoch we were using.
We did find what may have been a star while pointing at M13.  The
counts we very low (10 DN above sky), and we were not able to get
the feature satisfactorily centered in the fiber.  We used this
field to test a new sop procedure for generating instrument block
data. (By issuing offsets in a diamond pattern.)  We were able to
test the procedure with this field, but one of the early attempts
move the star to the edge of the fiber and we were not able to bring
it back to the center so we did not try guiding with this field
Toward the end of the night we tried to repeat the error we made with
the epoch to try and get the star back in the fiber so we could test
guiding, but we were unsuccessful.
Around 2am we lost tracking in the Az axis, but we able to get it back
with an axis init and reissuing the track command.
Before closing Connie did some mirror tests with the telescope at 86d.
altitude.  She will be sending a separate message about this.
Ellyne and Jeffrey