From: Russet McMillan Subject: 3.5m Night Log 20000402 Date: Mon, 3 Apr 2000 06:38:45 -0600 (MDT) Sunday, April 02, 2000 APACHE POINT OBSERVATORY Observing Log ACTUAL ASTRONOMER OBSERVER(S) INSTRUMENT DATE START FINISH -------------------------------------------------------------------- Tran Tsvetanov DIS(High) 4/02-03 --:-- --:-- Kron Kron SPIcam 4/03 01:00 05:54 INST SCHEDULED WEATH EQUIP OBS DAY NOTUSED I/RS/DN START FINISH D B D B D B USE D B -------------------------------------------------------------------- JH01/R 20:19 01:00 4.7 - 0 - - - 0 0 - UC02/S 01:00 05:54 0 - 0 - 4.9 - 0 0 - (note: times listed include instrument change time) -------- ACTIVITY LOG -------- First-Half Observing Specialists: C.Hastings Bad weather, that's all.... Second-Half Observing Specialist: R.McMillan The sky began to clear irregularly around 23:30, but snow had been seen within a mile of the site by observers driving in for the second shift, so opening was delayed until 00:50, too late to be any use to the first half observers. By this time the sky was very clear, but as late as 01:30, when DIMM was opened, the occasional snowflake was still drifting from clear air. * The DIMM measurements were reported with a timestamp in MST, even though both the DIMM laptop and galileo were both clocking MDT. Seeing in the first few focus and data images was moderate to poor, and out-of-focus images were extremely astigmatic (though the donuts were evenly illuminated -- see /export/images/kron0402/b0011.fits). With the telescope pointed directly into a 20 mph north wind, many examples of windshake were evident in the guider offsets. However, the guider seemed to do a good job of compensating, and the delivered seeing in 10-minute images was only slightly worse (1.4 arcsec) than the typical guider seeing in 5-second images (1.2 arcsec). As the target moved west and the wind moved east, both the short-term seeing and the delivered seeing improved dramatically. SPIcam, the guider and DIMM were all showing subarcsecond results for a while; once the wind settled, SPIcam was getting better seeing than the guider. For brighter guide stars, the signs of the shutter being open during chip readout or clearing were still evident. The telescope performance and guiding were quite good for the remainder of the night, with no need for a second focus. Cirrus began to move in after 05:00, thick enough to interfere with guiding. OBSERVER COMMENTS R. Kron (UC02): Observed two cluster candidates. Everything worked. FOCUS LOG April 02 2000 Wind Time Inst Focus Az El #Temp Dir MPH filt FWHM " ----------------------------------------------------------------------- 01:00 SPIcam -35(13) -58 64 -1.1/-0.4 346 9 i' 1.25 01:05 Guider -2000 #First temp is air, second temp is telescope. WEATHER April 02 2000 Wind Wind Time Temp F Dewp F MPH Direction Dust Sky Precip. ------------------------------------------------------------------- 23:01 30 23 5 319 (NW) 839 ptly cldy snow 00:01 30 22 9 334 (NNW) 810 mstly clr snow? 01:01 30 22 9 344 (NNW) 855 clear none 02:01 31 20 20 16 (NNE) 864 clear none 03:01 31 20 19 6 (N) 908 clear none 04:01 31 19 11 5 (N) 938 clear none 05:01 31 19 11 14 (NNE) 978 cirrus none 06:01 31 19 7 5 (N) 1008 cirrus 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 > 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: 2.55b5. Current guide software version: GIm Ctrlv3.0b27. Current TCC version is 2.2.2. - Camron Hastings, Russet McMillan