From: Subject: 3.5m Night Log 20081024 Date: Sat, 25 Oct 2008 13:22:45 +0000 (UTC) Apache Point Observatory 3.5m Telescope Night Log Friday, October 24, 2008 ACTUAL ASTRONOMER OBSERVER(S) INSTRUMENT START FINISH ------------------------------------------------------------------- J.Stockton J.Stockton DIS 18:45 00:45 C.Churchill J.Evans SPIcam 01:02 07:00 INST SCHED(TWILIGHT) WEATH EQUIP OBS DAY NOT USED I/ROW/DN START FINISH D B D B D B USE D B --------------------------------------------------------------------- NM04/R 19:14 01:00 0 0 0 0 5.8 0 0 0 0 NM09/R 01:00 06:21 0 0 0 0 3.1 2.3 0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- Observing Specialist: R.McMillan Another lovely clear night, this time with a few hours of fairly good seeing (just under 1 arcsec), although most of the night was moderate 1.2-1.5 arcsec and a couple of hours around midnight had 1.5-1.8 arcsec. Observing was smooth and mostly trouble-free. We had a couple of false alarms and one real (but small) problem with the rotator. The first false alarm was an "axis halted" noise from TUI at UT 02:06. When I checked, all axes were moving and I couldn't find any error messages, but I'm confident the noise wasn't imaginary, so I'm still baffled on that one. Later, at 03:25, a slew command failed because the rotator couldn't converge in 30 iterations. This isn't a true error, but an inherent shortcoming of our system that occasionally affects either az or rot when it's impossible for the software to determine which wrap direction to use. I advised the observer to change the rot wrap request in the Slew window from the default "Middle" to "Nearest" and the next slew was fine; after that, he went back to the default. After the instrument change, there was a genuine problem with the rotator failing to reinitialize correctly. It took several inits to recover from this, but the rotator was never lost; initialization difficulties are annoying, but not as troublesome as halts during slews or tracking. The time lost was probably less than two minutes so I just left it under the instrument change -- since the first half observer had ended a little bit early it worked out all right. ------- FAILURE LOG ------- PROG INST FAILURE MODE TIME (STEDFNVOG) TI/SHU START FINISH DESCRIPTION ---------------------------------------------------------------------- ---------------- FOCUS LOG --------------- Time Instrument Focus Az El Temp Strc Prim Sec Air filt FWHM ----------------------------------------------------------------------- 19:24 dis-slit -100( -23) 82 73 8.1 9.7 8.9 8.4 8.1 1.30 01:08 SPICAM -78( 134) -40 68 7.6 7.4 7.7 6.5 7.2 g 1.20 ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------- 16:00 50 12 9 280 (W) 231 clear none 17:00 48 12 8 244 (WSW) 278 clear none 18:00 48 12 4 346 (NNW) 294 clear none 19:00 47 10 10 329 (NNW) 328 clear none 20:00 47 11 14 316 (NW) 347 clear none 21:00 49 11 18 306 (NW) 364 clear none 22:00 48 11 7 325 (NW) 382 clear none 23:00 48 11 12 315 (NW) 394 clear none 00:00 47 11 3 243 (WSW) 414 clear none 01:00 46 11 7 348 (NNW) 455 clear none 02:00 45 11 9 24 (NNE) 450 clear none 03:00 44 11 11 23 (NNE) 405 clear none 04:00 45 8 19 0 (N) 454 clear none 05:00 45 9 24 18 (NNE) 577 clear none 06:00 45 6 14 358 (N) 540 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: 2.9.1 Current TUI version: TUI 1.5.1