Date: Fri, 4 Jun 1999 06:06:33 -0600 (MDT) From: Russet McMillan Subject: 3.5m Night Log 990603 Apache Point Observatory, Sunspot, NM Thursday, June 3, 1999 3.5-meter Night Observing Log Actual ---------------------------------------------------------------------- ASTRONOMER OBSERVER(S) INSTRUMENT DATE START FINISH ---------------------------------------------------------------------- Tripp Tripp Echelle 6/3-4 21:47 01:10 Gonzales Wallerstein Echelle 6/4 01:10 03:12 Turner McMillan SPIcam 6/4 03:22 04:15 ---------------------------------------------------------------------- INST SCHEDULED WEATH EQUIP OBS DAY NOTUSED I/RS/DN START FINISH D B D B D B USE D B ---------------------------------------------------------------------- PU05/R 21:48 01:10 0 0 0.8 0 1.2 1.4 0 0 0 UW06/S 01:10 03:17 - 0 - 0 - 2.1 0 - 0 PU03/S 03:17 04:15 - 0 - 0 - 1.0 0 - 0 -------------- Activity Log -------------- * Indicates that a problem report has been issued. Observing Specialist: R.McMillan The weather tonight was lovely, with clear skies, low dust, and decent seeing (with the echelle). The telescope pointed and tracked well. During first half, Todd Tripp was doing a very faint object on the echelle. We had some trouble with the slitviewer, apparently associated with taking long images. We got two 120-second images before it bombed out, and a dialogue box appeared on the slitviewer Mac saying that a file server connection had closed. The first echelle exposure was lost because of no guiding. For the next exposure, I did the guiding locally and shortened the slit viewer exposure to 100 seconds (with an autoexpose interval of 108 seconds). This worked. The next exposure, Todd tried to guide again with 100/108 seconds, and after about 10 slit viewer iterations the same problem came up. I managed to revive the slit viewer long enough to make a few guiding corrections before it was lost again; despite the constant struggle with the slit viewer, this echelle exposure turned out well. For the fourth echelle exposure, I guided once more with 60-second exposures, without trouble. So in spite of about 1.5 hours of frantic activity, only one exposure was lost, and three good ones were obtained. Craig has partially diagnosed this problem, and it is related to a timeout during long exposures (although the inconsistency still troubles me -- two successful 120-second images, and a few dozen 100-second images without trouble). The symptoms started (once again) with CAMERA BUSY in the slit viewer window, but the most distinctive characteristic was the dialogue box on the slit viewer Mac. The recovery procedure was rather complex and never fully hammered out; it would be preferable to avoid this problem altogether rather than try to correct it once it shows up. Until a genuine fix is worked out, I recommend not attempting slit viewer images long than 1 minute. It was possible to guide fairly well on a 16th magnitude object at one minute, by displaying the images through IRAF rather than depending on the Remark autodisplay with its unfriendly grayscale. During second half, George Wallerstein was observing much brighter targets which did not require such a long slit viewer exposure time. Interestingly, we did get some complaints of CAMERA BUSY on the last object (around 03:05), with a 5-second exposure time, but the autoexpose loop continued by itself without further intervention. I don't know what the complaint was about that time; I was not aware of any user error or other possible cause. Finally, we were able to get some lens observation data in the morning, although the low altitude and changing temperatures contributed to poor seeing. OBSERVER COMMENTS FOCUS LOG June 3 1999 Best Telescope Temp Wind Seeing Time Instrmnt Focus Az El Air/Truss Dir MPH filter FWHM" --------------------------------------------------------------------- 21:15 Echelle -16(5916) 19 56 16.1/16.2 223 19 clear 1.52 23:15 Echelle -32(5804) -5 59 14.7/14.4 266 12 clear 1.28 00:35 Echelle 11(5838) -20 55 14.0/13.8 269 13 clear 1.25 03:20 SPIcam -125(6583) 110 34 12.1/12.6 222 16 r' 1.49 WEATHER LOG June 3 1999 Wind Time Temp-F Dewp-F MPH Direction Dust Sky Precip ------------------------------------------------------------------ 16:01 68 21 21 252 (WSW) 728 clear none 17:01 68 21 23 207 (SSW) 736 clear none 18:01 67 22 23 216 (SW) 701 clear none 19:01 65 22 15 255 (WSW) 641 clear none 20:01 61 22 13 215 (SW) 771 clear none 21:01 61 22 15 223 (SW) 855 clear none 22:01 60 18 11 244 (WSW) 1273 clear none 23:01 59 15 11 266 (W) 1076 clear none 00:01 58 8 9 256 (WSW) 858 clear none 01:01 57 5 9 246 (WSW) 689 clear none 02:01 57 2 13 239 (WSW) 506 clear none 03:01 56 2 11 231 (SW) 540 clear none 04:01 54 9 18 216 (SW) 651 clear none 05:01 53 11 9 201 (SSW) 633 clear none 06:01 51 14 17 200 (SSW) 816 clear none 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: 2.55b5 Current guide software version: GIm Ctrl v3.0b 18.out - RM