Date: Fri, 5 Nov 2004 06:52:21 -0700 (MST) From: Jack Dembicky Subject: 3.5m Night Log 20041104 Apache Point Observatory 3.5m Telescope Night Log Thursday, November 4, 2004 ACTUAL ASTRONOMER OBSERVER(S) INSTRUMENT START FINISH -------------------------------------------------------------------- P.Hodge D.Zucker SPIcam 17:15 23:55 M.Strauss J.Hennawi DIS 00:15 06:20 INST SCHEDULED WEATH EQUIP OBS DAY NOT USED I/RO/DN START FINISH D B D B D B USE D B --------------------------------------------------------------------- UW06/R 18:04 00:00 0 0 0.7 0.1 4.5 0.7 0 0 0 PU05/R 00:00 05:30 0 0 0 0.5 0 5.0 0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- 1st Half Observing Specialist: J.Barentine Clear skies from the start tonight, light winds, seeing holding steady around 1.0 arcsec with excursions down to 0.6 and up to as high as about 1.3 arcsec. At 22:40, Dan informed me that he just received an unfamiliar SPIcam error message: "error in EXP-LEFT? answer, trying UNIX clock!". As to what the software was doing at the time, Dan wrote: "The (readout) time left isn't really incrementing, it just drops by 30 seconds every so often (maybe every 30 sec)". That suggested a timing problem. Dan indicated that the readout didn't appear to be progressing; header info was being written to the screen, but the usual readout progress lines weren't showing up. A minute or two later, he wrote that the software returned "CCD controller isn't responding; aborting read". At that point, the file 110404.0042.fits appeared on disk with a truncated file size, suggesting the header had been written but all the pixel info was dumped. I asked Dan to exit and restart the software. He did, trying another exposure, but the same symptoms recurred. Exposure 42 (saved as 110404.0042_safe.fits in /export/images) partially read out when Dan issued a "read" command in the SPIcam software, for a total file size of 5760 bytes. Normal SPIcam files in 2x2 binning are I copied aside the image as he intended to overwrite it, then got Craig. Dan started up another exposure, which began with the same error message as above. We let it read out, but as readout began, he got an error "camera not connected", and was then dumped out to a dryrot: prompt. Craig had me go upstairs to check the state of the filter wheel on a hunch; turned out that the wheel was energized, but not moving. I barely touched the wheel and it started moving again. Evidently the filter wheel move Dan commanded at 22:34 never completed because the wheel hung for some reason, and there is no timeout in the software. The later commands were not acknowledged because of this. With Craig on the phone, I ran the wheel around several times from the Observing Level but noticed not the slightest hint of resistance in its motion. With Craig's blessing I buttoned it up and headed downstairs with the caveat that we would be on the lookout for a repeat of the problem. 2nd Half Observing Specialist: J.Dembicky Focus was varible when Joe started his run. He reported that the rotator seemed to be off by about 3 degrees in rotation and his first 30 min exposure was ruined because of this error. (no star in the slit). I told him that I will check the rotator in the morning to see how much it is off and if it is off by a significant amount I will credit his time lost as equipment failure. I then instructed him not to rely on the rotator and always check to make sure your targets are correctly aligned in the slit before exposing. At the end of the night I commanded DIS a rotation of zero, before I took it off. It was indeed off (visibly) by a couple degrees from zero. I put the level on the back of DIS and it was no where near level (confirming what I saw by eyeballing it). 3 degrees is probably not out of the question. John told me that he commanded SPIcam a zero rotation when he took it off at midnight and everything looked level with SPIcam, so something must have slipped early after DIS was mounted. ------- FAILURE LOG ------- PROG INST FAILURE MODE TIME (SEGDFVO) TI/SHU START FINISH DESCRIPTION ----------------------------------------------------------------------- UW06 S I/S 22:34 23:22 SPIcam filter wheel hung PU05 D T/H 00:30 01:00 Rotator off by about 3 deg not noticed until observers first exposure. ---------------- FOCUS LOG --------------- Air/Truss Wind Time Instrument Focus Az El Temp-C Dir MPH filt FWHM --------------------------------------------------------------------- 18:12 SPIcam 50(1295) 160 81 6.9/7.7 150 18 r' 0.80 18:15 NA2gdr -1250(35750)165 81 6.9/7.7 147 18 R 0.82 00:16 DISslit 0(1008) -54 66 6.4/5.3 177 23 - 1.2 00:18 NA2gdr -1261(29738)-55 65 6.3/5.3 164 20 R 0.83 ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------ 16:01 49 11 9 154 (SSE) 178 Clear none 17:01 45 11 13 125 (SE) 148 Clear none 18:01 45 -4 15 141 (SE) 110 Clear none 19:01 44 -10 19 146 (SE) 147 Clear none 20:01 45 -11 17 177 (S) 99 Clear none 21:01 44 -12 16 157 (SSE) 152 Clear none 22:01 42 -13 19 145 (SE) 250 Clear none 23:01 42 1 23 153 (SSE) 143 Clear none 00:01 42 3 19 163 (SSE) 101 Clear none 01:01 44 -3 23 176 (S) 67 Clear none 02:01 43 -2 19 173 (S) 124 Pt. Cldy none 03:01 42 -11 22 180 (S) 245 Pt. Cldy none 04:01 40 -7 22 161 (SSE) 265 Pt. Cldy none 05:01 39 -8 24 160 (SSE) 218 Pt. 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 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