From: Russet McMillan Subject: 3.5m Night Log 20060916 Date: Sun, 17 Sep 2006 05:53:36 -0600 (MDT) Apache Point Observatory 3.5m Telescope Night Log Saturday, September 16, 2006 ACTUAL ASTRONOMER OBSERVER(S) INSTRUMENT START FINISH ------------------------------------------------------------------- M.Klaene R.McMillan,G.Saurage SPIcam,S-H, 21:00 05:15 DIS,NA2gdr INST SCHED(TWILIGHT) WEATH EQUIP OBS DAY NOT USED I/ROW/DN START FINISH D B D B D B USE D B --------------------------------------------------------------------- EN01/W 20:02 05:55 0 0 0 0 6.1 3.8 0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- Observing Specialists: R.McMillan,G.Saurage This was a very successful night for shutdown recovery. Skies were clear and apparently photometric, and seeing was moderate to excellent. The new top end seems to be performing nicely. The telescope was balanced and last-minute wiring for the top end completed just around sunset. We opened the dome for cooling and started tests of basic functions after about 21:00. The az and alt drives were very noisy at first, but looked a little better after the velocity scales were measured -- this improvement was smaller for alt than for az. The velocity scales will need to be re-measured over the next few days as the telescope and drive disks continue to cool. After discussion with Mark, we decided not to bother with primary collimation. We did want to keep a close eye on the PMSS, but unfortunately the dataq had a repeating problem where it kept losing its connection. We had to proceed without a proper indication of the PMSS state, but we figured any gross problems would be visible on the images. Some high-frequency shivering was apparent at some positions that probably came from the PMSS (or possibly wind on the top end, but we hope not). There were also lower-frequency tracking oscillations in the altitude direction when the telescope was at high altitude. I played briefly with the altitude PID loop parameters without much effect. We had trouble at first finding a star with the Shack-Hartmann, so used Spicam to get a star reasonably centered with calib offsets. Then we focused spicam and got -2650 um compared to the previous instrument zeropoint (about -1700 um from the mirror's center of travel). The donuts at first looked reasonably symmetrical, but as the secondary pistoned closer to best focus the coma appeared worse. We went back to the Shack-Hartmann and adjusted tertiary tilts for pointing, then secondary tilts for a rough collimation (because it looked bad enough I wasn't sure the S-H could measure it accurately), then tertiary tilts again because changing the secondary tilts had changed the pointing. Finally we got real collimation measurements with the Shack-Hartmann, which indicated (among other things) that the seeing was really excellent. I decided to go for a Shack-Hartmann altitude sweep to take advantage of the conditions. In the process we covered a lot of secondary function tests. Mirror motion for piston and tilt changes appeared smooth and repeatable, with no backlash or twitching visible on the video. We obtained a Shack-Hartmann altitude sweep down to altitude 45 (despite good seeing, we couldn't get much lower because of what appeared to be PMSS oscillations). This will give us a start on new algorithms for focus dependence on altitude and secondary translation correction for mirror sag. I switched back to spicam to adjust pointing once more with calib offsets preparatory to taking a pointing model. However, once centered on spicam, the star wouldn't offset correctly to the guider. I spent about an hour struggling with this, and after attempting to get a guider instrument block I finally realized the guider had not recovered from software tests that apparently changed the windowing and binning -- so instead of looking at the full chip with 3x3 binning, I was looking at the bottom left 1/3 of the chip with 1x1 binning. I was fooled at first because the image sizes were the same. I checked and found that the command syntax looked correct for 3x3 binning, so something must be wrong at the command-interpretation level. I gave up attempting to work with the guider and switched to the next high priority item on the task list, throughput. I obtained spectra of a standard star with and without a slit for the B400+R300 grating combination (for which we have some pre-shutdown data sets to compare with). I also got another view of some DIS chip contamination that was worrying us, and which was hard to evaluate during the shutdown. Some moderately bad contamination is visible on the blue side, but it doesn't appear much different from before shutdown. On the red side, both stellar spectra and lamp spectra look all right -- so we don't seem to have any lingering problems from the ion pump failure that occurred around labor day (the ion pump was replaced and the dewar was pumped, but not baked, so there was some concern that contaminants might not have been fully cleared). Several of tonight's secondary-evaluation tasks will need to be repeated and refined in the coming nights; if seeing remains good, we might be able to get a better range on a Shack-Hartmann altitude sweep after the PMSS is tuned. Secondary translation will also need a thorough evaluation once implemented. One high-priority addition to the task list is drive tuning, especially in altitude. I spent only a little effort on this tonight, hoping that it will improve on its own as the telescope cools to a more normal temperature, and also wanting to concentrate on tasks which made use of the excellent weather conditions. But this is something that must be addressed more carefully in some way before we go to science. ------- FAILURE LOG ------- PROG INST FAILURE MODE TIME (SEDFNVOG) TI/SHU START FINISH DESCRIPTION ---------------------------------------------------------------------- ---------------- FOCUS LOG --------------- Air/Truss Wind Time Instrument Focus Az El Temp-C Dir MPH filt FWHM --------------------------------------------------------------------- 22:46 SPIcam -2650(-1544) 25 65 10.9/12.1 179 10 g 1.4 23:00 S-H -2870 good 01:36 SPIcam -2750(-1650) 147 47 9.4/10.3 222 11 r 0.79 04:01 DISslit -2790(-1809) 41 58 11.0/10.1 263 3 - 1.15 ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------- 16:00 64 35 13 239 (WSW) 144 clear none 17:00 60 35 11 260 (W) 201 clear none 18:00 59 33 9 261 (W) 231 clear none 19:00 55 26 15 242 (WSW) 162 clear none 20:00 53 25 12 199 (SSW) 148 clear none 21:00 52 27 10 218 (SW) 185 clear none 22:00 53 24 10 179 (S) 175 clear none 23:00 52 24 11 183 (S) 200 clear none 00:00 51 20 13 200 (SSW) 178 clear none 01:00 49 26 14 216 (SW) 202 clear none 02:00 50 30 16 217 (SW) 265 clear none 03:00 51 25 10 212 (SSW) 280 clear none 04:00 52 23 5 265 (W) 243 clear none 05:00 51 28 6 336 (NNW) 216 clear 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 > 1u per 0.1 cubic feet. TELESCOPE STATUS Telescope drives operational. Current TCC version: 2.8.4 Current TUI version: TUI 1.2