From: "Camron Hastings" Subject: 3.5-meter Night Log 980920 Date: Mon, 21 Sep 1998 06:57:41 -0600 Sunday, September 20th 1998 APACHE POINT OBSERVATORY 3.5-meter Observing Log ACTUAL ---------------------------------------------------------------------- ASTRONOMER OBSERVER(S) INSTRUMENT DATE START FINISH ---------------------------------------------------------------------- T.Wyder T.Wyder SPIcam 9/20-21 20:25 00:20 E.Turner C.Hastings SPIcam 9/21 00:20 01:10 A.Tomaney A.Tomaney SPIcam 9/21 01:10 05:29 ---------------------------------------------------------------------- INST SCHEDULED OBS WEATH EQUIP DAY NOTUSED I/RS/DN START FINISH D B D B D B USE D B ---------------------------------------------------------------------- UW05/R 20:25 00:20 3.9 0 0 0 0 0 0 0 0 PU01/S 00:20 01:10 0 0 0.8 0 0 0 0 0 0 UW06/R 01:10 05:28 3.2 0 1.1 0 0 0 0 0 0 -------- ACTIVITY LOG -------- 1st half observing specialist: Karen Gloria The telescope was opened at 20:15 MDT. Opening was delayed by unsettled weather. We had rain late in the afternoon and threat of more showers into early evening. The quality of the seeing was poor to average, ranging from about 1.3 to 1.8 arcsec. There were a lot of cattle at the site. 2nd half observing specialist: Camron Hastings I took over to cloudy skies, and failing to pierce the clouds for the Lens Monitoring program, I decided to close the telescope at 01:00 until the weather improved. We opened again at 02:15 and remained so. Clouds were high and fast all night, we really need that cloud cam back, as some of these fast clouds contain rain! Each morning I have left to find one lone, gray cloud dripping in a very localized area... --------- OBSERVER COMMENTS --------- Ted Wyder (UW05): Except for the clouds and variable seeing, everything went well. The telescope, guider and SPIcam worked well. I'd also like to include a few comments about my data from Friday as others may find it interesting. After having a chance to look at my data from Friday, Sep. 18, I realized that there seems to be a problem with the twilight sky flats that I obtained before sunrise. When I use them to flat-field my data, there is about a 10% (!) gradient in the sky in my U, B and V images of my science targets. This gradient is not in the un-flat fielded images and is present in the flats. The only explanation that I can come up with is that the new baffling is still letting in some scattered light. I'm not entirely sure why, but the R flats seem to be fine. Even though the sky in my target images is brighter in R, there is no gradient present after dividing by the R-band flat. Perhaps this is because I obtained the R flats first before the sky got too bright. A.Tomaney (UW06): SPIcam performed flawlessly throughout the night. The offsets required to centre SPIcam look to be around (+42" RA, -21" DEC). The camera also looks like it requires a +2 deg rotation to align it N-S. Battled some cloud during the night. Seeing varied from 1-1.4". Managed to cover most of my targets. FOCUS LOG September 20th 1998 Best Telescope Temp Wind Seeing Time Instrmt Focus Az El Air/Truss Dir MPH filter FWHM" ---------------------------------------------------------------------- 20:30 SPIcam -250(6430) 13 55 13.0/15.4 218 15 V 1.4" 22:20 SPIcam -150(6372) 85 74 12.2/12.6 209 11 V 1.3" 22:25 Guider 50600(6372) 85 75 11.9/12.7 216 14 R 1.5" 23:15 SPIcam -050(6547) 359 50 12.5/12.4 221 17 V 1.4" 02:25 SPIcam -070(6421) -46 78 11.7/12.0 273 11 rjt 1.1" 02:40 Guider 49991(6421) -46 78 11.8/12.0 267 10 - 1.2" WEATHER LOG September 20th 1998 Wind Time Temp-F Dewp-F MPH Direction Dust Sky Precip ------------------------------------------------------------------ 16:01 62 37 14 271 (W) 474 cloudy rain 17:01 50 49 5 317 (NW) 2440 cloudy rain 18:01 54 45 13 274 (W) 390 mstly cldy none 19:01 54 47 10 234 (SW) 700 ptly cldy none 20:01 53 47 11 195 (SSW) 794 ptly cldy none 21:01 55 47 12 213 (SSW) 606 ptly cldy none 22:01 53 47 14 182 (S) 629 ptly cldy none 23:01 56 47 16 241 (WSW) 685 ptly cldy none 00:01 55 47 11 249 (WSW) 837 mstly cldy none 01:01 54 49 11 238 (WSW) 801 cloudy none 02:01 53 47 10 253 (WSW) 801 mostly clr none 03:01 53 45 5 277 (W) 822 mostly clr none 04:01 53 43 16 285 (WNW) 985 ptly cldy none 05:01 53 45 13 280 (W) 1179 ptly cldy none 06:01 52 45 12 285 (WNW) 1306 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