Date: Thu, 25 Feb 1999 06:34:53 -0700 (MST)
From: Russet McMillan
Subject: 3.5m Night Log 990224
		     Apache Point Observatory, Sunspot, NM
		         Wednesday, February 24th, 1999
                          3.5-meter Night Observing Log
				  Actual
----------------------------------------------------------------------
ASTRONOMER       OBSERVER(S)     INSTRUMENT      DATE    START  FINISH
----------------------------------------------------------------------
C.Stubbs         C.Hastings      SPIcam        2/24      19:18  20:08
D.Leeber         D.Leeber        GRIM II       2/24-25   20:28  05:14
----------------------------------------------------------------------
 INST       SCHEDULED      WEATH     EQUIP      OBS     DAY    NOTUSED
I/RS/DN   START  FINISH    D    B    D    B    D    B   USE    D    B
----------------------------------------------------------------------
EN02/S    19:18  20:18     -    0    -    0    -   1.0   0     -    0
NM05/S    20:18  05:14     0    0    0   0.3  2.2  6.5   0     0    0
               -------------- Activity Log --------------
1st Half Observing Specialist: N.C.Hastings
	We opened at 16:30 for cooling. Dale had GRIM back on line for
tonight's program and it seems to be behaving well. I was the observer
for the UW program, and clouds hindered us all night. Dawn Leeber was
on site to observe for NMSU. The seeing monitor was also set up
tonight by APO staff, myself. We had a two errors with file writing
that were easily corrected. Observing went smoothly and only the
clouds interfered.
2nd Half Observing Specialist: R.McMillan
After NM05's main object of interest had set, with cirrus preventing
accurate photometry, they decided to switch to DIS.  In the process,
we discovered that the calibration lamp controls had not survived the
LAN switchover on Saturday.  Since the purpose of the spectroscopy was
just to do spectral classifications, the observer elected to continue
using DIS even without arc lamps.
Interesting note: DIS apparently dumped its nitrogen while it was
mounted, because at dawn it was 20 lbs lower than usual for that time
of day.  But it didn't dump *all* its nitrogen, and it didn't warm up.
This could be consistent with the theory that the dumps occur when the
instrument is at some undesirable rotation during one of the scheduled
fills.  Tonight, the second half program included many short exposures
on bright stars -- so perhaps DIS moved either to or from that
undesirable rotation value in the middle of a fill.  If my
calculations are correct (using the fill time obtained through "dis
ln2 status"), the fill started at 03:49.
			   OBSERVER COMMENTS
T.Harris (NM05):
Given the appearance of the weather at sunset, it is surprising that we were
able to observe all night. Dawn Leeber used GRIM to observe V616 Mon for
the first half of the night. Due to the cirrus, we decided to switch to DIS
since our second half objects needed photometry. We observed 17 different
objects with DIS and obtained excellent spectra.
                               FOCUS LOG
                           February 24th 1999
                  Best    Telescope    Temp      Wind          Seeing
Time  Instrmnt   Focus      Az  El   Air/Truss  Dir MPH  filter FWHM"
---------------------------------------------------------------------
18:55  SPIcam  -250(6120)  092  46   3.6/5.8    268  09    V    1.59"
19:02  Guider 52000(6077)  093  47   3.6/5.7    263  06   none  1.64"
20:28  GRIM II -180(6236)  190  56   4.9/4.9    234  09  J-f/5  0.72"
01:45  DIS     -200(6132)  186  57   5.3/5.0    290  23  Gunn   0.94
                              WEATHER LOG
                           February 24th 1999
                                  Wind
     Time   Temp-F Dewp-F MPH   Direction    Dust      Sky     Precip
   ------------------------------------------------------------------
     16:01    48     5     10   269  (W)      823  mstly cldy   none
     17:01    43     1      8   315  (NW)     806  mstly cldy   none
     18:01    41     0      5   281  (W)      913   ptly cldy   none
     19:01    38    -2      8   267  (W)      810    cirrus     none
     20:01    41     0      6   264  (W)      817    cirrus     none
     21:01    41     0      9   221  (SW)     711    cirrus     none
     22:01    41     0      9   228  (SW)     894    cirrus     none
     23:01    42     0      8   265  (W)      756    cirrus     none
     00:01    42     0     14   273  (W)      648    cirrus     none
     01:01    42     0     15   264  (W)      600    cirrus     none
     02:01    42     1     16   273  (W)      589    cirrus     none
     03:01    42     1     20   284  (WNW)    555    cirrus     none
     04:01    42     1     18   280  (W)      536   ptly cldy   none
     05:01    42     0     16   269  (W)      637  mstly cldy   none
     06:01    42     1     12   268  (W)      617  mstly cldy   none
note: the wind was coming from the azimuth listed.  The convention
used is north=0 degrees, east=90 degrees. The dust count is for the
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: 2.54b4
Current guide software version: GIm Ctrl v3.0b 17.out
- NCH, RM