Date: Fri, 11 Sep 1998 08:14:24 -0600
From: Karen Gloria
Subject: 3.5-m obslog 980910
                        THURSDAY SEPTEMBER 10, 1998
                         APACHE POINT OBSERVATORY
                              OBSERVING  LOG
                                                          ACTUAL
ASTRONOMER      OBSERVER(S)        INSTRUMENT   DATE   START FINISH
T. Harrison   Harrison/Johnson        DIS     9/10-11  21:30  05:21
                 McNamara
 INST        SCHEDULED      OBS      WEATH     EQUIP   DAY   NOTUSED
I/RS/DN    START FINISH   D    B    D    B    D    B   USE   D    B
NM06/R     20:40  05:21  0.7  2.0  0.8  4.5  0.5  0.2   0    0    0
(note: times listed include instrument change time)
                               ACTIVITY LOG
(* means a trouble report has been issued or appended to)
1st half observing specialist: Camron Hastings
2nd half observing specialist: Karen Gloria
	The enclosure was opened at 21:30 after being delayed by
clouds and rain showers earlier this evening.  *Right before opening,
NM06 mentioned that the bias images were increasing in mean count
levels, and when they told me, they were nearing saturation.  Tom
suggested a possible dewer failure, and I agreed.  Upon checking, the
getters had reached their max safe limit to refill, so I hurried
upstairs to see if I could initiate the fills.  I found the transfer
dewer completely full, but 0.0 psi within the tank.  I checked all
valves, and they seemed fine.  I used a large filler LN2 tank as a
pressure source and DIS began filling as normal.  While filling, I did
notice very small, low pressure bubbles coming from around one of the
machine screws. The water soon froze solid though.  I left the large
LN2 tank attached in case it is needed as a pressure source
again. After the fills, it took about 30 mins for both cameras to
stabilize, and NM06 began focusing at 21:50.
	We closed again at 22:40 due to humidity above 85%, dew point
depression below 2.2C, and moisture being felt in the enclosure.  Tom
was very sad...to say the least...
	- Camron Hastings
	*I squirted some soapy water on the machined block on top of
the xfer dewar.  The nylon seal is leaking around the outside edge and
around the screws.  I tightened the screws a little.  This helped but
there is still a slow leak.  Humidity continued to rise.  I think that
as long as we have this East wind we will continue to get moisture
from T.S. Frances.
	The wind shifted a little to the north and the humidity
dropped enough to open the telescope at 3:10 MDT.  *here was a problem
with the compressed air supply but the pressure didn't drop enough to
affect the primary mirror support system.  The pointing was 50 arcsec
off in altitude on the first field.  We noticed this after the first
spectrum didn't look right.  No problems after that.
	- Karen
			     OBSERVER COMMENTS
NM06 (Tom Harrison) - "After a shutdown due to high humidity, Karen
called me at 3am to tell me we could again observe. I really
appreciate this, as it allowed me to finally finish (the NMSU TAC goes
"HURRAH" here) my HST dwarf novae calibration observations. Now that
this tortured project is over, I am sure everyone will have clear
skies for the remainder of '98. Thanks Karen.
	DIS performed nominally except for the coolant problem
encountered earlier in the night."
                                 FOCUS LOG
                             SEPTEMBER 10 1998
                  Best   Telescope           Wind            Seeing
Time   Inst      Focus    Az  El   #Temp    Dir MPH  filter  FWHM "
21:50  DIS      0(6562)   52  69 11.7/12.4   72  19   none  ~1.3"
3:45   DIS    100(6743)   316 48 12.6/11.5   34  16    r     1.3
#The first temp is air, the second is truss, both in degrees Celsius
                                 WEATHER
                             SEPTEMBER 10 1998
                               Wind
     Time   Temp F Dewp F  MPH   Direction   Dust      Sky      Precip.
     16:01    53    47     11    79  (ENE)    664   Altocumulus  Rain
     17:01    51    48     13    76  (ENE)    816   Altocumulus  Light
     18:01    54    44     10    86  (E)      554   Altocumulus  None
     19:01    53    48     10    88  (E)     1216   Altocumulus  None
     20:01    53    47     15    75  (ENE)   1275   Lt AltCumls  None
     21:01    53    48     13    80  (E)     1478   Lt AltCumls  None
     22:01    53    48     15    79  (ENE)   1480     Light      None
     23:01    52    48     10    79  (ENE)   1845     clear      none
     00:01    51    49     14    74  (ENE)   2027     clear      none
     01:01    51    49     14    71  (ENE)   2552     clear      none
     02:01    50    49     15    61  (ENE)   3048     clear      none
     03:01    53    45     12    44  (NE)    1699     clear      none
     04:01    55    --     18    31  (NNE)   1152     clear      none
     05:01    54    43     18    56  (NE)    1270     clear      none
     06:01    52    46     12    63  (ENE)   1760     clear      none
     07:01    51    47     15    65  (ENE)   1905     clear      none
     08:01    54    47     12    52  (NE)    1483     clear      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: 2.41a.
Current guide software version: GIm Ctrlv3.0b15.
-Camron Hastings, Karen Gloria