From: Russet McMillan
Subject: 3.5m Night Log 20000510
Date: Thu, 11 May 2000 05:51:10 -0600 (MDT)
                          WEDNESDAY MAY 10, 2000
                         APACHE POINT OBSERVATORY
                              OBSERVING  LOG
                                                          ACTUAL
ASTRONOMER      OBSERVER(S)        INSTRUMENT   DATE   START FINISH
Krisciunas	Rest		   SPIcam, GRIM 5/10   20:51  01:00
Austin		Austin		   DIS		5/11   01:00  05:08
 INST        SCHEDULED     WEATH     EQUIP      OBS    DAY   NOTUSED
I/RS/DN    START FINISH   D    B    D    B    D    B   USE   D    B
UW02/R     20:51  01:00   -    0    -    0    -   4.2   0    -    0
WS01/R     01:00  05:08   0   0.5   0    0   2.7  0.9   0    0    0
(note: times listed include instrument change time)
                              ACTIVITY LOG
Observing Specialist: McMillan
Experiments with the PMSS during the afternoon showed some coupling
between motions of the A and C sectors of the primary mirror and
various triggers such as the cooling fans or people moving in the
dome.  Attempts to tune the PMSS had some success but didn't
completely eliminate all oscillations.
The telescope was opened before sunset for cooling under clear skies.
The weather remained clear all night, with variable seeing -- we
obtained undersampled images with GRIM at f/5, but both SPIcam and DIS
showed worse seeing than the concurrent DIMM measurements.  Some
images were worse than 2 arcseconds.
As noted before, bias images taken with SPIcam showed a strong
correlation between noise and umbilical position.  See
/export/images/lowz_sn/may11/bias.0002.fits for an example of an image
with the GRIM umbilical in a position which is convenient for
instrument changes.  When GRIM was pushed further aside and the
umbilical hung from the wall (which produces delays when changing
instruments), the noise was greatly reduced (e.g. bias.0007.fits)
In images obtained during first half, multiple examples of image
elongation were seen, but never so bad as to make the images unusable.
Some images were round; the elongation could come and go on timescales
of a few seconds, as seen in focus images.  While DIS was in use, some
elongation was nearly always present in slitviewer images, and
tracking was distinctly poor.  In addition to the known problems with
the rotator and PMSS, some of these problems may have been caused by
windshake, since the winds were fairly high all night long.
The telescope was closed for half an hour shortly after 3 am due to
high winds.  Several communications failures between here and WSU
occurred during second half, eventually necessitating some service
observing.  The network problems were evident in broken ftp and web
connections as well as Remark, although both sites seemed to be able
to communicate with the rest of the world fairly consistently.
                            OBSERVER COMMENTS
                                FOCUS LOG
                                                 Wind
Time  Instrument  Focus     Az  El   #Temp     Dir MPH  filt  FWHM "
20:30 SPIcam     -20(   )  219  54  16.7/17.6  270  25   V    1.39
23:10 GRIM(f/5)    0(852)           15.3/15.6  267  27   J    1 micron per 0.1 cu. ft.
                             TELESCOPE STATUS
Primary, secondary, and tertiary mirrors in place and collimated.
Primary support system operational.  Mirror ventilation system in
place.  Telescope drives operational.  Current Remark version: 2.55b5.
Current guide software version: GIm Ctrlv3.0b27.  Current TCC version
is 2.2.5.
- Russet McMillan