Date: Tue, 27 Oct 1998 05:57:41 -0700 (MST) From: Russet McMillan Subject: 3.5m Night Log 981026 Content-Length: 3162 MONDAY OCTOBER 26, 1998 APACHE POINT OBSERVATORY OBSERVING LOG ACTUAL ASTRONOMER OBSERVER(S) INSTRUMENT DATE START FINISH Turner McMillan SPIcam 10/26 - - York Nichols DIS 10/26 - - Rizza Rizza SPIcam 10/27 - - INST SCHEDULED OBS WEATH EQUIP DAY NOTUSED I/RS/DN START FINISH D B D B D B USE D B PU01/S 18:41 19:31 0 0 0 0.8 0 0 0 0 0 UC08/R 19:31 00:10 0 0 2.0 2.6 0 0 0 0 0 NM02/S 00:10 04:54 0 0 0 4.7 0 0 0 0 0 (note: times listed include instrument change time) ACTIVITY LOG (* means a trouble report has been issued or appended to) observing specialist: Russet McMillan It started raining around 18:00, and after that only let up long enough to tease. At the beginning of the night, Dan Long and I adopted radical methods (a Kim-wipe and an anti-dust canister) to get the condensation off SPIcam's window. In the process, we realized that the filter box (which receives the nitrogen blow-off) and the dewar window (which has the lingering condensation) are separated from each other by the shutter. So naturally, nitrogen blow-by while the shutter is closed won't do the dewar window much good (see last night's log). So tonight I left the shutter open for long periods with the nitrogen flowing past. This seemed to work adequately for preventing further condensation, but doesn't tell us much about efficiency of evaporation. The only major drawback is the effect the venting has on the big nitrogen tank. DIS was unfortunately allowed to warm during the night because I was only checking the weight of its dewar rather than noting the pressure. I did monitor the CCD temperature during the evening, but failed to check it during second half. Eventually I realized the little scale was stuck, but by that time the temperature was up to 200K. I turned the instrument off to be pumped during the day. OBSERVER COMMENTS FOCUS LOG OCTOBER 26 1998 NO FOCUS INFORMATION WEATHER OCTOBER 26 1998 Wind Time Temp F Dewp F MPH Direction Dust Sky Precip. 16:01 50 39 20 223 (SW) 193 cloudy rain 17:01 47 39 16 180 (S) 109 cloudy rain 18:01 47 40 13 192 (SSW) 170 cloudy rain 19:01 45 43 4 196 (SSW) 122 cloudy rain 20:01 42 42 9 217 (SW) 5872 cloudy rain 21:01 41 41 10 191 (S) 1215 cloudy rain 22:01 42 42 16 201 (SSW) 1862 cloudy rain 23:01 42 42 12 183 (S) 9069 cloudy rain 00:01 42 42 18 201 (SSW) 30 cloudy none 01:01 43 41 18 157 (SSE) 51 cloudy none 02:01 45 39 14 186 (S) 36 cloudy rain 03:01 42 42 10 263 (W) 108 cloudy rain 04:01 41 39 7 200 (SSW) 9 cloudy rain 05:01 40 40 7 335 (NNW) 175 cloudy rain note: the wind was coming from the azimuth listed. The convention used is north=0 degrees, east=90 degrees. The dust count is 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 Ctrlv3.0b15. -Russet McMillan