From: Russet McMillan Subject: 3.5m Night Log 20000117 Date: Tue, 18 Jan 2000 06:48:07 -0700 (MST) MONDAY JANUARY 17, 2000 APACHE POINT OBSERVATORY OBSERVING LOG ACTUAL ASTRONOMER OBSERVER(S) INSTRUMENT DATE START FINISH Davis Staff video 1/17 18:18 20:05 Krisciunas Krisciunas GrIm2 1/17 20:05 21:05 Davis Staff video, S-H 1/17-18 21:05 06:08 Echelle INST SCHEDULED WEATH EQUIP OBS DAY NOTUSED I/RS/DN START FINISH D B D B D B USE D B EN01/S 18:18 20:05 - 0 - 0 - 1.8 0 - 0 UW07/R 20:05 21:05 - 0 - 0 - 1.0 0 - 0 EN01/S 21:05 06:08 0 0 0 0 1.8 7.3 0 0 0 (note: times listed include instrument change time) ACTIVITY LOG (* means a trouble report has been issued or appended to) 1st half observing specialist: Loomis The telescope was opened at 17:30 MST with some high clouds in the sky. The beginning of the night was used to examine image motion with a video camera at the NA2 port. We didn't see any large excursions, but we did see a low amplitude (about .5"), high frequency jitter that appears to be caused by the air flowing through the primary mirror. We also saw our star move 10" up in altitude when the fans were turned off, indicating that the suction due to the air flow was uneven on the back of the mirror. Jon Davis covered up a mirror cell access port that was open. This reduced by almost 1/2 the distance the star moved when the fans were turned off. We entered the new 2ndary x-tilt coefficients and took some more Shack-Hartmann data. Kevin Krisciunas observed for UW07, with GrIm2, for an hour. The seeing was pretty good. 2nd half observing specialist: McMillan Second half started out mostly clear with excellent seeing, then clouds moved in around 05:00. We put in the X tilt coefficients and were planning to do a pointing model with the echelle slitviewer, but we noticed right away that out-of-focus images looked grossly out of collimation (in fact, the value of 0.75 arcseconds below was for focus with bad collimation). A quick analysis of the first half Shack-Hartmann data showed asymmetry in Y as well as X, even though our values for the Y tilt had seemed quite good on January 8. We spent a while playing with different X and Y tilts at several altitudes, but concluded that we didn't have enough time to try to improve on the fit obtained from the previous data. So we put in the requested coefficients for X and changed the Y tilt from +100 to +75 and left it at that. Next, I obtained three pointing models with the new tilts, each one covering a successively greater range of altitude. All three models returned RMS errors of 8-9 arcseconds, and all three included a large number of missed stars on the first try. However, zeroing the calibration offset was usually sufficient to find the star, so the models were nearly complete and should be sufficient to bring targets onto the instrument. The exception was that in the last model, extending down to an altitude of 20 degrees, several of the lowest stars had to be skipped entirely. There was cirrus around by that time, so I don't know if the problem was pointing or clouds at high airmass. By the time the third pointing model was done, only ten minutes remained until twilight. There was no time for an AOTF instrument block, and I didn't think there was enough time to obtain enough S-H data with the new coefficients to improve on what we got at the end of first half. So I just did some spot-checking of the pointing at different positions. In two positions in the west, the star did not come up on the slitviewer at first, but over the course of 20-30 seconds slowly drifted into view. Images giving examples of this motion and several other motions have been saved, and a more detailed description will be sent to techstaff. OBSERVER COMMENTS FOCUS LOG JANUARY 17 2000 Wind Time Inst Focus Az El #Temp Dir MPH filt FWHM " 20:15 GrIm2 50(1203) 273 65 8.9/9.2 295 7 K' 0.50 00:15 Echelle 96(274) -8 50 8.2/8.0 298 15 ND2 0.75 #First temp is air, second temp is telescope. WEATHER JANUARY 17 2000 Wind Time Temp F Dewp F MPH Direction Dust Sky Precip. 16:01 54 13 6 277 (W) 569 ptly cldy none 17:01 51 13 3 290 (WNW) 630 ptly cldy none 18:01 48 9 4 344 (NNW) 591 ptly cldy none 19:01 48 5 6 337 (NNW) 647 ptly cldy none 20:01 48 7 6 323 (NW) 583 ptly cldy none 21:01 48 7 6 269 (W) 589 ptly cldy none 22:01 48 8 7 271 (W) 733 ptly cldy none 23:01 48 9 9 267 (W) 789 ptly cldy none 00:01 47 11 14 295 (WNW) 800 mstly clr none 01:01 47 12 14 294 (WNW) 849 mstly clr none 02:01 47 15 10 293 (WNW) 927 mstly clr none 03:01 46 15 9 320 (NW) 908 mstly clr none 04:01 46 16 10 308 (NW) 815 cirrus none 05:01 48 18 10 297 (WNW) 562 cirrus none 06:01 48 18 11 295 (WNW) 582 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. - Karen Loomis, Russet McMillan