From:
Subject: 3.5m Night Log 20091225
Date: Sat, 26 Dec 2009 13:30:44 +0000 (UTC)
                        Apache Point Observatory
                        3.5m Telescope Night Log
                        Friday, December 25, 2009
                                                            ACTUAL
 ASTRONOMER      OBSERVER(S)            INSTRUMENT       START  FINISH
 ---------------------------------------------------------------------
 J.Greene        J.Greene               Tspec            17:15  23:36
 R.Reyes         R.Reyes                DIS              00:05  06:15
   INST     SCHED(TWILIGHT) WEATH     EQUIP      OBS     DAY  NOT USED
 I/ROW/DN   START  FINISH   D    B    D    B    D    B   USE   D    B
 ---------------------------------------------------------------------
 PU06/R     17:12  00:00    0    0    0    0    0   6.8   0    0    0
 PU02/R     00:00  06:55    0    0    0    0   5.2  1.7   0    0    0
 note: scheduled times listed include instrument change time
                ------------- ACTIVITY LOG --------------
 Observing Specialist: R.McMillan
 A peaceful and productive night, photometric throughout with
 variable seeing (mostly poorish).
 For our holiday dinner, we had a cookie assortment and crackers with
 cheese; eggrolls and a green salad; gingersnap-and-mustard crusted
 ham and orange-scented green beans and tuscan risotto and scalloped
 sweet potatoes; fudgy brownies and green tea cake and pumpkin pie;
 mulled cider and two special-blend iced teas.  Quite a spread for
 only four diners!
 The telescope and instruments worked well, but there were some
 interesting features of guiding with both instruments.  Guiding with
 Tspec was somewhat temperamental as usual, but interestingly it was
 better when guiding on extended targets so long as the cores were
 still centroidable.  For the extended targets, there was a large
 offset to get sky spectra, and frequently the guiding would fail to
 identify the object at the sky offset position (even though the
 guide object was still on the chip), but it would reliably come back
 to the same place if we didn't mess with it or if it didn't fail
 over to manual mode.  This is the familiar problem with
 medium-to-large offsets that we've seen for some time, but I still
 wasn't quite able to tell if the problem was an inaccurate
 instrument block (which is on our engineering task list to redo) or
 the differential distortions of the slitviewer.  I do believe I can
 say, IF the problem is in the instrument block it must be rotation
 and not scale.
 With DIS guiding, we had multiple problems of changing to invalid
 guide stars.  Several (most?) of these occurred when the observer
 changed the slitviewer exposure time during guiding, and then the
 guide software would "change guide star" to either the left-hand
 bright artifact or the upper-right corner for reasons that are
 unclear to me.  I think there were a couple of instances that did
 not correspond to changes in exposure time, but the exposure change
 did seem to be a fairly reliable trigger of the problem.  I
 documented one of these cases in the still-open problem report.
 I was pleased to note no apparent problems with the DIS slitviewer
 despite the cold temperatures.
                      ------- 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
--------------------------------------------------------------------------
 04:44 TSPEC   125( -188) -129  22  -4.8 -5.7 -5.1 -5.6 -5.0     2.10
 00:10 dis-slit   194( -573)  74  74  -7.1 -7.5 -7.1 -7.8 -7.5   1.00
                ------------- WEATHER LOG ----------------
                                   Wind                      Precip.or
     Time   Temp F Dewp F  MPH  Direction    Dust    Sky    Conditions
    -------------------------------------------------------------------
     16:00    21    16      4   288  (WNW)    437    clear     none
     17:00    18    14     16    26  (NNE)    687    clear     none
     18:00    17    14     14     4    (N)   1020    clear     none
     19:00    16    12     14    14  (NNE)    693    clear     none
     20:00    16    10     17     2    (N)   1149    clear     none
     21:00    16     9     16   327  (NNW)    650    clear     none
     22:00    16     8      9   340  (NNW)    882    clear     none
     23:00    16     8     12   331  (NNW)    586    clear     none
     00:00    17     6     21   331  (NNW)    368    clear     none
     01:00    17     3     11   342  (NNW)    342    clear     none
     02:00    18     1     17   324   (NW)   1139    clear     none
     03:00    20    -5     16   350    (N)    317    clear     none
     04:00    21   -11     16   324   (NW)    670    clear     none
     05:00    24   -18     15    21  (NNE)    215    clear     none
     06:00    21   -15     15   312   (NW)    514    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 > 1u per 0.1 cubic feet.
                              TELESCOPE STATUS
      Telescope drives operational. Current TCC version: 2.11.1
      Current TUI version: TUI 1.6.2