Date: Thu, 4 Nov 2004 05:47:39 -0700 (MST) From: John Barentine Subject: 3.5m Night Log 20041103 Apache Point Observatory 3.5m Telescope Night Log Wednesday, November 3, 2004 ACTUAL ASTRONOMER OBSERVER(S) INSTRUMENT START FINISH -------------------------------------------------------------------- J.Frieman J.Marriner DIS 18:00 23:58 G.Stringfellow G.Stringfellow GRIM 00:00 05:35 INST SCHEDULED WEATH EQUIP OBS DAY NOT USED I/RO/DN START FINISH D B D B D B USE D B --------------------------------------------------------------------- UC01/R 18:05 00:00 0 0 0 0 4.2 1.7 0 0 0 CU04/R 00:00 05:29 0 0 0 0.6 0 4.9 0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- Observing Specialist: J.Barentine Tonight was mostly quiet, with periods of excellent seeing (0.6 arcsec on the NA2 guider) to bursts of >2 arcsec at times when the wind died to almost nothing. Everything went well until around 03:20, when Guy and I noticed that a significant focus change occurred over a short time interval. Autocollimation was turned on at the time. Secondary focus appeared to change by several hundred steps; the guider went out by almost 8000 steps. Out of focus star images were somewhat distressing, suggesting something had gone awry with collimation. The centering of the secondary shadow seemed to change over time scales of a few minutes, while out of focus donuts on the guider looked distinctly pinched. However, checking with the SDSS observers, they also noted a strong focus change around the same time. I fiddled with the focus for about 15 minutes before deciding that there was in fact no hardware problem and had Guy carry on. By this time, the focus values had returned to roughly where they were previously. ------- FAILURE LOG ------- PROG INST FAILURE MODE TIME (SEGDFVO) TI/SHU START FINISH DESCRIPTION ----------------------------------------------------------------------- CU04 D T/H (?) 03:20 03:55 Rapid, large focus change ---------------- FOCUS LOG --------------- Air/Truss Wind Time Instrument Focus Az El Temp-C Dir MPH filt FWHM --------------------------------------------------------------------- 18:07 DISslit 200(1185) 228 79 3.6/5.1 7 14 - 0.82 18:10 NA2gdr -50(30950) 231 78 3.7/5.0 18 10 R 0.58 00:21 NA2gdr -50(30950) 125 41 7.4/5.6 147 0 R 2.07 00:21 DISslit -50(1063) 125 41 7.4/5.6 147 0 - 1.34 03:50 DISslit 0(1147) 206 49 8.5/7.1 192 1 - 0.87 03:52 NA2gdr 0(33100) 207 49 8.5/7.1 189 1 R 1.11 ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------ 16:01 41 -8 2 18 (NNE) 0 Clear none 17:01 39 -8 13 358 (N) 0 Clear none 18:01 38 -5 13 33 (NNE) 66 Clear none 19:01 40 -2 18 20 (NNE) 61 Clear none 20:01 43 -7 16 14 (NNE) 48 Clear none 21:01 41 -4 14 32 (NNE) 246 Clear none 22:01 42 -5 12 30 (NNE) 67 Clear none 23:01 46 -17 1 329 (NNW) 9 Clear none 00:01 44 -12 0 191 (S) 42 Clear none 01:01 46 -13 5 122 (ESE) 22 Clear none 02:01 45 -13 1 121 (ESE) 24 Clear none 03:01 47 -20 2 199 (SSW) 11 Clear none 04:01 48 -20 3 188 (S) 18 Clear none 05:01 48 -22 5 177 (S) 24 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. Note: Tower dust counter is down. No readings were available. TELESCOPE STATUS Telescope drives operational. Current Remark version: 2.85b Current TCC version: 2.7.2 Current TUI version: TUI 0.92