From: "Camron Hastings" Subject: 3.5-meter Night Log 980919 Date: Sun, 20 Sep 1998 05:53:30 -0600 Saturday, September 19th 1998 APACHE POINT OBSERVATORY 3.5-Meter Observing Log ACTUAL ---------------------------------------------------------------------- ASTRONOMER OBSERVER(S) INSTRUMENT DATE START FINISH ---------------------------------------------------------------------- D.York G.Richards DIS 9/19-20 20:27 01:10 H.Newberg G.Richards DIS 9/20 01:10 05:28 ---------------------------------------------------------------------- INST SCHEDULED OBS WEATH EQUIP DAY NOTUSED I/RS/DN START FINISH D B D B D B USE D B ---------------------------------------------------------------------- UC01/R 20:27 01:10 4.7 0 0 0 0 0 0 0 0 UC02/R 01:10 05:28 2.2 0 2.1 0 0 0 0 0 0 -------- ACTIVITY LOG -------- 1st half observing specialist: Karen Gloria The telescope was opened at 20:10 MDT after spectral calibrations. The seeing was as bad tonight as it was good last night. Average seeing was about 2 arcsec with star images constantly blooming in and out. Other than the poor seeing, everything was fine. There were no telescope or equipment problems. Peter Doherty fixed the SPIcam shutter problem today. He and I tested the shutter this afternoon and it works. 2nd half observing specialist: Camron Hastings I took over the telescope at 23:45 this evening. Clouds gradually thickened, at times obscuring the object, but usually OK. We again had problems with the telescope dragging in one axis. When I would re-init the axes, I would notice an extremely high slew time considering we were already on the correct coords. Slew times would be from 80-100 secs. My theory is that the newly initiated rotator limits are allowing it to wrap the cables up somewhat, and the way the cables are hanging is causing a excessive torque on the rotator. The de-rotation after the init seemed to alleviate this. I previously measured the rotation force to on the collar while at horizon, and was suprised to find that in the cable pull direction, a force of 22lbs was necessary, but in the opposite direction only 8lbs was necessary. Quite a disparity, possibly too much at places. Anyway, the clouds were a bigger problem, and despite both, we obtained a few spectra. I also tested out a new IRAF package created by Gordon Richards to help with DIS spectra reductions. It seems to install smoothly and what I tried worked well. If interested in this, get in touch with Gordon at U Chicago. --------- OBSERVER COMMENTS --------- (UC01)(UC02) G.Richards: A reasonably productive night given the cloud cover and a few rotator problems. The red RN was up to 22.5 electrons though. FOCUS LOG September 19th 1998 Best Telescope Temp Wind Seeing Time Instrmt Focus Az El Air/Truss Dir MPH filter FWHM" ---------------------------------------------------------------------- 20:50 SlitCam -100(6746) 89 61 14.8/17.5 265 9 none 2.0" 21:05 guider 52200(6854) 132 35 15.6/17.1 238 10 none 2.3" WEATHER LOG September 19th 1998 Wind Time Temp-F Dewp-F MPH Direction Dust Sky Precip ------------------------------------------------------------------ 16:01 70 38 13 271 (W) 279 ptly cldy none 17:01 65 37 8 274 (W) 235 ptly cldy none 18:01 68 39 7 266 (W) 288 ptly cldy none 19:01 62 36 9 269 (W) 322 ptly cldy none 20:01 60 38 9 260 (W) 362 ptly cldy none 21:01 58 38 8 262 (W) 405 ptly cldy none 22:01 61 37 9 227 (SW) 395 ptly cldy none 23:01 61 36 11 247 (WSW) 371 ptly cldy none 00:01 61 35 8 268 (W) 387 ptly cldy none 01:01 60 35 8 270 (W) 470 ptly cldy none 02:01 57 36 10 301 (WNW) 431 mstly cldy none 03:01 58 33 8 310 (NW) 346 mstly cldy none 04:01 57 35 4 337 (NNW) 461 ptly cldy none 05:01 56 34 6 344 (NNW) 411 ptly 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 for the particles > 1 micron per 0.1 cu.ft. TELESCOPE STATUS Primary, secondary, and tertiary mirrors in place and collimated. Primary support system operational. Mirror ventilation system in place. Telescope drives operational. Current Remark version: 2.42a Current guide software version: GIm Ctrl v3.0b 15.out - Karen Gloria, Camron Hastings