Date: Tue, 03 Oct 2000 06:37:57 -0600 From: "s. a. snedden" Subject: 2.5 m obs log 20001002 (MJD 51820) Monday, October 2, 2000 Apache Point Observatory SDSS 2.5m Observing Log (MJD 51820) OBSERVING TEAM: =============== Stephanie Snedden (APO) Dan Long (APO) Eric Neilsen (JHU) Mike Harvanek (APO) VISITORS: ========= Michael Strauss (PU) Bill Boroski (FNAL) John Peoples (FNAL) Dave Schlegel (PU) THE PLAN: ========= Science. Imaging has high priority, but we will start with spectroscopy during moony conditions. SYNOPSIS FOR NIGHT: =================== Spectroscopy. More rotator problems, but we worked around them. Patchy clouds through the night kept us from switching to imaging. Four plates were observed, but only three were declared done. TELESCOPE STATUS: ================= Stowed at 30 deg alt with cartridge 4 mounted. Counterweights at 270. INTERLOCKS: =========== None bypassed SOFTWARE USED: ============== IOP/SOP: v3_18_4_1 Watcher: v2_8_6 MCP: v4_3_2 at first, then v4_3_8 TPM: v2_1_2 AstroDa: 14_34 TCC: 2.4.0b2 WEATHER SYNOPSIS (see below for hourly data): ============================================= Partly cloudy until about 22:00. Then clear to mostly clear until about 02:00. Then partly to mostly cloudy. GENERAL COMMENTS (see Problems below for details): ================================================== Skies were not photometric at sunset, however we had to start with spectroscopy anyway, because of Moon. We mounted cartridge 4, plate 359. While trying to acquire the field, the rotator aborted (while tracking). This occurred at about 20:30. At this time, we were using the "old" MCP (v4_3_2). We switched back to the latest version, v4_3_8. A lot of time was spent getting an FK5 star down a guide fiber using the old MCP version. Once the latest MCP was booted, we had no trouble acquiring the field. We still had high drive voltage conditions for the rotator, however (see problems section). We had another ion pump pressure spike, but it never got high enough to trigger a critical error (see Problems section). We kept hoping that conditions would improve for imaging, but this did not happen. Cartridge 4, plate 359: ----------------------- Calib offsets: az=0.005403 deg, alt=-0.000066 deg Taken at 21:45 (approx.) scale factor: 1.00016 Three science exposures were taken, but we were working at high airmass, as a result of the time taken up acquiring the field. Therefore we didn't achieve the required S/N to declare this plate done. The rotator voltage kept building, and we would have had rotator aborts during these exposures, but Dan moved the rotator a few degrees back then forward and then to the nominal position while exposing. This lowered the voltage, and prevented aborts. Cartridge 5, plate 429: ---------------------- Calib offsets: az=0.004885 deg, alt=0.003273 deg at 23:18 Scale factor: 1.00007 Three science exposures were taken. Seeing went subarcsecond at times on the fibers! Unfortunately, this happened at the same time that some clouds rolled in, so although we were tempted to switch to imaging, it was not meant to be. We had no rotator aborts with this cartridge, and the rotator voltage value decreased with time. The rotator angles were also decreasing. Dan noted that when the rotator was moving to higher angles, as with the previous cartridge, this was where we had problems with the rotator voltage. This cartridge took 5 science exposures. sp1 red had very low S/N compared to the other chips. It also had a bright object, which we think depressed the S/N. The true S/N may be much higher, but we decided to take no chances. This cartridge was declared done. Cartridge 2, plate 400: ----------------------- Calib offsets: az=-0.004996 deg, alt=-0.001845 deg at 01:30 scale factor: 0.99992 We had no problems with this plate, and declared it done with three science exposures (there were no extremely bright objects, either). This sequence had no rotator aborts or high rotator voltage conditions. Again, the rotator was moving from high to lower rotator angles. Cartridge 9, plate 407: ----------------------- Calib offsets: az=0.001460 deg, alt=0.001203 deg at 03:20 scale factor: 1.00002 Again, we had no rotator problems, and again, we were moving in the negative direction. We did have opaque clouds move in, which reduced our efficiency. It took six exposures to declare this plate done. DATA ACQUISITION (see IOP/SOP output below): ============================================ IMAGING: -------- Run # Frames Type --- -------- ---- 1756 35 bias - taken with imager on telescope. Time approx 18:00 1757 35 bias - taken with imager in doghouse. Time approx 21:30 SPECTROSCOPY: ------------- Exposure Type -------- ---- 6831 bias *** Cartridge 4, plate 359 *** 6832 bias 6833 pre-flat 6834 pre-arc 6835 science 6836 science 6837 science 6838 smear 6839 post-flat 6840 post-arc 6841 pre-flat *** Cartridge 5, plate 429 *** 6842 pre-arc 6843 science 6844 science 6845 science 6846 science 6847 science 6848 smear 6849 post-flat 6850 post-arc 6851 pre-flat *** Cartridge 2, plate 400 *** 6852 pre-arc 6853 science 6854 science 6855 science 6856 smear 6857 post-flat 6858 post-arc 6859 pre-flat *** Cartridge 9, plate 407 *** 6860 pre-arc 6861 science 6862 science 6863 science 6864 science 6865 science 6866 science 6867 smear 6868 post-flat 6869 post-arc TAPES: ====== JL3095 to be shipped JL3102 at APO MIRRORS: ======== PRIMARY: -------- MIGS Axial A= 1.9305 Axial B= 0.5590 Axial C= 0.5559 Transverse D= 0.3944 Lateral E= 1.9155 Lateral F= 0.4165 GALILS Commanded: 5127.,-2930.,404.,-5854.,14576.,14124 Actual: 5150., -2950., 400., -5850., 14600., 14100. SETMIR VALUES primDesOrient: 0.00, -8.00, 11.70, 640.50, 439.70 primOrient: 0.00, -8.36, 11.84, 640.32, 439.52 SECONDARY: ---------- Focus: -200 Temp: 16.7 Altitude: 44.9 MIGS Axial A= -1.1030 Axial B= -0.9929 Axial C= -1.0529 Transverse D= 0.2290 GALILS Commanded: 1251869.,1213275.,1283861.,-2491.,-7302. Actual: 1251801., 1213345., 1283908., -2500., -7300. SETMIR VALUES secDesOrient: 991.90, -20.00, -8.00, 50.00, 2.80 secOrient: 991.92, -20.01, -7.96, 49.91, 2.88 FOCUS LOG: ========== M1 Piston M2 Piston Temp Wind Time Inst setmir TCC setmir Az Alt C Dir MPH filt FWHM 21:45 sp cart4 0.00 -300 909.4 225.2 41.8 16.5 240 9.4 1.5" 22:45 sp cart4 -2171.5 -250 -805.5 223.9 32.9 15.5 244 11 1.8" 23:20 sp cart5 -2171.5 -250 -934.3 71.8 49.5 15.7 261 12 1.6" 00:15 sp cart5 -295.2 -250 660.1 58.6 59.2 15.5 278 17 1.1" 00:50 sp cart5 0.00 -250 890.7 44.8 65.2 15.1 269 7.3 1.4" 01:45 sp cart2 790.0 -200 1613.3 1.0 57.3 14.9 218 5.3 1.2" 02:45 sp cart2 790.0 -200 1613.5 5.0 57.2 15.6 266 6.8 1.2" 03:20 sp cart9 -196.4 -300 699.8 17.8 55.9 15.9 267 8.4 1.4" 04:20 sp cart9 -196.4 -300 713.0 -36.1 51.4 16.1 271 5.6 1.5" 05:10 sp cart9 -591.5 -300 412.8 -52.7 43.2 16.2 275 8.0 1.4" LN2 SCHEDULE: ============= Spectros filled at 06:00. Weight 108 lb. Imager dewar weight at 06:00 134 lb. WEATHER DATA: ============= Wind Time Temp F Dewp F MPH Direction Dust DIMM Sky Precip. ---- ----- ----- -------------- ---- ---- --- ------ 16:01 70 30 20 257 (WSW) 312 - pcl none 17:01 68 30 11 269 (W) 367 - pcl none 18:01 67 31 13 267 (W) 412 - pcl none 19:01 62 31 5 266 (W) 429 - pcl none 20:01 62 31 6 269 (W) 469 - pcl none 21:01 62 30 11 235 (SW) 449 - mclear none 22:01 61 30 12 211 (SSW) 385 - clear none 23:01 60 30 8 256 (WSW) 478 - clear none 00:01 60 30 9 265 (W) 531 - pcl none 01:01 60 31 7 264 (W) 514 - pcl none 02:01 59 31 7 224 (SW) 553 - pcl none 03:01 60 30 9 270 (W) 1405 - mcl none 04:01 61 30 5 272 (W) 1383 - mcl none 05:01 62 29 7 269 (W) 1258 - mcl none [pmt]cl = partly, mostly, totally cloudy PROBLEMS: ========= Rotator Aborts: --------------- We had one rotator abort at about 20:30. The rotator angle was 54 degrees. We would have had more aborts, but whenever the drive voltage got too high, Dan moved the rotator a few degrees back and forth, then back to the nominal position, which reduced the rotator drive voltage to acceptable levels. This is a workaround that can only be used for spectroscopy, of course. Tonight, these high drive voltages only occurred when the rotator was moving from low to higher rotator angles (cartridge 4). On subsequent exposures where the rotator was moving toward decreasing angles, we had no problems. As a result, we would have tried imaging in the east, (such that the rotator moved toward decreasing angles), but clouds kept us from doing this. Imager Ion Pump Pressure: ------------------------- We had an instance where the ion pump pressure went up to 1.24 microtorr, then subsided to 1.0 microtorr. According to Connie, this coincided with the dismounting of the imager from the telescope. Starting at about 01:30, the pressure increased again, reaching a maximum of 1.20 microtorr at 03:30. It subsided toward 1 microtorr through the rest of the night. MCP Azimuth Fiducial (PR 1416): ------------------------------- Dan noticed that anytime the azimuth has a negative value and crosses a fiducial, it does not appear to have a valid table entry. He thinks some logic needs to be added or the fiducial table needs to be expanded to handle the negative values ( like adding 360 to negative az values to look up the fiducial ). See errors in the murmur log like Oct 03 02:19:52 sdssmcp tLatch dsc_I_trcInfo az fiducial -14.35 deg Oct 03 02:19:52 sdssmcp tLatch dsc_I_trcInfo Applying correction 3859884 to azimuth Oct 03 02:19:52 sdssmcp tLatch dsc_E_trcErr correction for azimuth 3859884 is too large A PR was filed. RUNLOGS: ========