From: Russet McMillan
Subject: 3.5m Night Log 20000416
Date: Mon, 17 Apr 2000 06:53:10 -0600 (MDT)
                          SUNDAY APRIL 16, 2000
                         APACHE POINT OBSERVATORY
                              OBSERVING  LOG
                                                          ACTUAL
ASTRONOMER      OBSERVER(S)        INSTRUMENT   DATE   START FINISH
Stephens        Stephens	   GRIM	      4/16-17  20:30  05:35
 INST        SCHEDULED     WEATH     EQUIP      OBS    DAY   NOTUSED
I/RS/DN    START FINISH   D    B    D    B    D    B   USE   D    B
NM03/S     20:30  05:35   -    0    -    0    -   9.1   0    -    0
(note: times listed include instrument change time)
                              ACTIVITY LOG
Observing Specialist: McMillan
Tom Stephens was on site to observe with GRIM.  Some of our visitors
from LLNL worked in the dome preparing the FTS until shortly after
18:00.  The dome was opened at 19:00.  Aside from a few user
errors, the telescope and instrument generally behaved well; * there
was one crash of the GRIM application during cals which cost no images
and little time.
The weather was mostly clear, with some very thin clouds starting
shortly after midnight -- not enough to require longer integration
times, but enough to affect photometry.  The seeing was excellent
almost all night, with the telescope (both guider and instrument)
getting consistently better measurements than DIMM.  A few short
exposures actually showed a FWHM of less than 0.5 arcseconds, which
was beginning to be undersampled even with GRIM at f/10.
* We had multiple rotator runaways during the night, both in the first
slew at checkout and during later slews.  Most of them were small and
self-correcting, but one move overshot the destination by more than 40
degrees.  Over the past month or so, these runaways have been getting
more common.  It would be nice to have some idea of what's causing
them.
I had some trouble starting up DIMM; it failed to find Polaris and
begin measurements with the smallsearch and bigsearch routines, yet
when I checked in the finder, Polaris was very closed to being
centered.  There was also trouble with the clock on the laptop, which
apparently is not being correctly set by the routine that compares
with the time on galileo.
The good seeing made us very sensitive to focus changes, especially as
the telescope temperature changed.  The primary mirror was cooler than
the air at sunset, so the telex fans were left off at first and then
forgotten until after 23:00.  The rapid change in focus is reflected
in the log below.  It was also apparent that there was some difference
in focus for the different filters in GRIM, particular when moving
between broadband (J and K) and narrowband (e.g. 1.57, 1.70, 1.65)
filters.
Since the seeing was so good, I experimented with changing the binning
on the guider and found that the guiding routines work well with
different binning.  However, the guider focus routine and the guider
monitor (especially the FWHM measurement) both failed to acknowledge
the change in binning.
                            OBSERVER COMMENTS
                                FOCUS LOG
                              APRIL 16 2000
                                                  Wind
Time  Instrument  Focus     Az  El   #Temp    Dir  MPH  filt  FWHM "
21:40  GRIM     500(1173)  207  61  9.8/10.7  208   17   J    0.60
23:15  GRIM     400(975)   292  81  9.4/9.4   186    8   J    0.62
23:55  GRIM     100(689)   308  86 10.1/9.2   225   11   J    0.56
01:25  GRIM     200(806)   217  76 10.0/9.8   236   12   K    0.66
#First temp is air, second temp is telescope.
                                 WEATHER
                              APRIL 16 2000
                               Wind
     Time   Temp F Dewp F  MPH   Direction    Dust      Sky      Precip.
     17:01    61    13     13   252  (WSW)    876      clear      none
     18:01    58    13     13   198  (SSW)    959      clear      none
     19:01    53     9     10   230  (SW)    1065      clear      none
     20:01    49     4     14   209  (SSW)   1029      clear      none
     21:01    50     5     16   204  (SSW)    900      clear      none
     22:01    49     5     12   197  (SSW)    914      clear      none
     23:01    49     4      9   188  (S)      945      clear      none
     00:01    51     5     12   221  (SW)     980      clear      none
     01:01    51     7      8   254  (WSW)    968    lt cirrus    none
     02:01    50     6     10   224  (SW)     905    lt cirrus    none
     03:01    50     7     12   233  (SW)    1010    lt cirrus    none
     04:01    49     7     12   232  (SW)    1063    lt cirrus    none
     05:01    49     6     10   243  (WSW)   1061      cirrus     none
     06:01    49     7      7   270  (W)     1138    lt cirrus    none
note: the wind was coming from the azimuth listed.  The convention
used is north=0 degrees, east=90 degrees.  The dust count is particles
> 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