Date: Sun, 6 Jun 1999 04:33:02 -0600 (MDT)
From: Ellyne Kinney
Subject: 2.5m obslog 990605 (MJD 51335)
			Saturday, June 5, 1999
		Apache Point Observatory SDSS 2.5m
			  Observing Log
Observing Team:   Ellyne Kinney (APO)
		  Matt Newcomb (CMU)
		  Charlie Briegle (FNAL)
		  Russell Owen (UW)
Tonight we tried more guiding tests.  We we had plate 122 plugged for Field
J (205,0).  We were on the sky at 9pm MDT. We started out by trying to
acquire a nearby FK5 star (203.67329,-0.59594) in fiber 10 by using the
starInFiber command in SOP.  We were unable to get a star in this fiber
even after trying several offsets including the offset that worked Friday
night (-.002,-.0015,-.105).
Just on the off chance that it might work we tried to acquire field J
directly, and found a donut shape from a badly out of focus star in gfiber
10.  The focus was set at 575 and after some experimentation we settled on
a focus of -350.  At this point we had stars down all fibers.  We then ran
the commands in sop to create an updated instrument block for the guide
fibers and updated the instrument block.  We then started guiding.  The
guiding started off pretty well, but after 20min, the stars wandered off
the fibers.
It was decided that stars in fibers 1, 2, 3, and 11 we fainter than the
others, so we turned disabled these fibers and centered back up on the
field.  We required an offset of  -.002,-.004,-.105 to center the stars in
the fibers.  We restarted guiding.  The guiding went very well and we let
it run of ~1hour.  At this point field J was too far over, so we replugged
the plate for field L (241,0).
We were unable to get any stars down the fibers in this field.  We tried
centering on a nearby FK5 star (244.58038, -4.69250), as well as the field
we tried removing the pointing correction from the previous field, adding
offsets in a box pattern in 5" steps and sweeping though the focus in the
range of -1000 to 1000.  We also tried loading the instrument block
created on Friday for this field.  We had no luck with any of these
attempts.
When the telescope was stowed for the night we checked the fiducial
settings in Az and Alt in the MCP.  The Az and Alt values were right on
target.
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Ellyne K. Kinney
SDSS Observer			INTERNET: ekinney@apo.nmsu.edu
Apache Point Observatory 	Voice: (505) 437-6822
Sunspot, NM 88349
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