Date: Mon, 9 Mar 2009 04:39:18 -0600
Subject: 3.5m Night Log 20090308
From: Jeff Coughlin
                     Apache Point Observatory
                     3.5m Telescope Night Log
                     Sunday, March 8, 2009
                                                        ACTUAL
 ASTRONOMER     OBSERVER(S)              INSTRUMENT  START  FINISH
 --------------------------------------------------------------------
 N.Chanover     C.Miller                 SPICAM      --:--  --:--
  INST     SCHED(TWILIGHT) WEATH     EQUIP      OBS     DAY  NOT USED
 I/ROW/DN   START  FINISH   D    B    D    B    D    B   USE   D    B
 --------------------------------------------------------------------
 NM01/R     19:59  06:28   0.1  10.4  0    0    0    0    0    0    0
 note: scheduled times listed include instrument change time
               ------------- ACTIVITY LOG --------------
 Observing Specialist: J. Coughlin
 Had completley opaque clouds all night. Light rain\hail began to fall
 around 20:00, and turned to slushy snow by 21:00. We got up to maybe
 1/4" of accumulation, but temp stayed around +0.3-0.5C and snow was
 melting by 01:00. Given this, predicted high of 50F tomorrow, and high
 winds, I didn't feel it was necesary to run the snow program as it
 should all melt tomorrow. By 4am humidity was still 100%, and radar and
 satelitte showed no hope of clearing, and so I closed for the night.
 I had an observer inquire about the dark current for Spicam, and I
 noticed there was no dark current rate listed in the documentation.
 (Obviously it's nearly negligible due to its low operating temp), but
I thought I'd
 use the down time to measure it. I derived a value of 5.6 DN per
pixel per hour =
 18.9 e- per pixel per hour. Maybe this can be put in the documentation
 so that observers know its likely pointless to take darks cals unless they
 are taking really, really long exposures.
 I think the weather log may be off by an hour as well, likely due to
 daylight savings bug.
                      ------- FAILURE LOG -------
 PROG   INST   FAILURE MODE     TIME
      (SEDFNVOG)   TI/SHU    START  FINISH  DESCRIPTION
 ----------------------------------------------------------------------
              ---------------- FOCUS LOG ---------------
 Time  Instrument  Focus    Az  El  Temp Strc Prim  Sec  Air  filt FWHM
 -----------------------------------------------------------------
               ------------- WEATHER LOG ----------------
                                  Wind                      Precip.or
    Time   Temp F Dewp F  MPH  Direction    Dust    Sky    Conditions
   -------------------------------------------------------------------
     16:00    38    21     21   222   (SW)    301 mstly cldy   none
     17:00    38    23     26   225   (SW)    283 mstly cldy   none
     18:00    37    23     20   245  (WSW)    330   cloudy     none
     19:00    37    25     14   231   (SW)    239   cloudy   lt rain
     20:00    34    30     18   231   (SW)    278   cloudy   lt rain
     21:00    33    31      9   234   (SW)    285   cloudy   lt snow
     22:00    32    32     23   214   (SW)    358   cloudy   lt snow
     23:00    33    32     27   219   (SW)   6158   cloudy     snow
     00:00    33    33     32   209  (SSW)   3583   cloudy     snow
     01:00    33    33     29   204  (SSW)   1330   cloudy     snow
     02:00    33    33     38   219   (SW)  11694   cloudy     none
     03:00    33    33     25   212  (SSW)   2969   cloudy     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 > 1u per 0.1 cubic feet.
                             TELESCOPE STATUS
     Telescope drives operational. Current TCC version: 2.10.0
     Current TUI version: TUI 1.5.1