Date: Thu, 21 Sep 2000 07:48:49 -0600 From: "s. a. snedden" Subject: 2.5m obslog 20000920 (MJD 51808) Wednesday, September 20, 2000 Apache Point Observatory SDSS 2.5m Observing Log (MJD 51808) OBSERVING TEAM: =============== Stephanie Snedden (APO) Atsuko Nitta Kleinman (APO) Bing Chen (JHU) VISITORS: ========= Chris Gelino (NMSU) THE PLAN: ========= Shakedown. Get a good pointing model and test the *OPs. SYNOPSIS FOR NIGHT: =================== Mostly clear skies but horrid seeing for the first half. Better seeing, but variable clouds for the second half. A pointing model was obtained, but we encountered many rotator aborts during the night. TELESCOPE STATUS: ================= Stowed at 30 deg alt with engineering camera mounted. Counterweights at 120. INTERLOCKS: =========== None bypassed SOFTWARE USED: ============== IOP/SOP: v3_18_3 Watcher: v2_8_5 MCP: v4_3_6 TPM: v2_1_0 AstroDa: 14_34 TCC: 2.4.0b2 WEATHER SYNOPSIS (see below for hourly data): ============================================= Mostly clear at sunset, but horrid seeing. Seeing improved after midnight, but clouds moved in two hours before twilight. Cool temperatures. GENERAL COMMENTS (see Problems below for details): ================================================== Very, very bad seeing (averaging 4 asec) to start. We attribute this to the lack of thermal management provided by the lava lamp. This prevented us from even being able to find centroids for the pointing model stars. Since the wind was out of the east, we tried a seeing test that occurred to Dan during the last dark run. We closed the west door of the enclosure while we were open in hopes that it would keep warm air from the blower outlet from being blown back to the telescope. Unfortunately, we did not see any noticable change in FWHM when we did this. The rotator spontaneously aborted while tracking and slewing several times. See the problems section for details. At about 23:00, the seeing improved to about 3 asec (DIMM) and was barely good enough to try taking pointing data. We completed a 70 point model under marginal seeing conditions. Shortly after we finished, the wind shifted and seeing improved. Since we feel it is very important to get as good a pointing model as possible to see if we can acquire stars faster for spectroscopy, we decided to take a second set of pointing data. While taking the first set of pointing data, it appeared that active fiducial corrections were being properly applied. During the second set, azimuth corrections stopped being made about midway through the set. As a result, the first set gave better RMS errors, and we decided to load it after three outliers were removed. Halfway through the second batch of pointing data, we had to thrash with more rotator aborts at a rot angle of 151 deg. We think this is also when the azimuth corrections stopped, but the murmur log should be checked more closely to verify this. When we finally resolved the rotator abort problem (see problems section), we found that clouds had moved in. #$%^&!!! Then the dust counts rose and started to flirt with the closure limits. We took the last points of the model with the dust counts bouncing around just under 3000, then closed as twilight was starting. The pointing model results: * getdat p6.dat Read 66 data points * fit coeff change value sigma 1 IE +0.450 -185.11 1.333 2 IA +0.344 -233.76 1.450 3 AN +0.081 -5.48 0.436 4 AW -0.181 -55.97 0.446 5 HWCA2 +0.002 +0.47 0.556 6 HWSA2 -0.432 -0.63 0.613 7 HNCA1 -0.317 -0.15 0.661 8 HNSA1 +0.173 +1.76 0.672 9 CA -0.410 +6.09 1.079 10 PZZ1 +0.065 -130.89 4.084 11 ACEC +0.066 +1.16 0.800 12 ACES +0.042 -0.39 0.808 13 TX +0.140 -3.44 1.861 Sky RMS = 2.33 Popn SD = 2.60 Jim Gunn called during the evening and requested that the spectro biases be checked. A few extra biases were taken and looked at for excess noise. They appeared to be okay, since the means and standard deviations were consistent with historical values. Note to spectro pipeline folks: We need feedback on the spectro data taken during moony conditions the last night of the last dark run DATA ACQUISITION (see IOP/SOP output below): ============================================ IMAGING: -------- Run # Frames Type --- -------- ---- 1713 36 bias - p.m. checkout SPECTROSCOPY: ------------- Exposure Type -------- ---- 6565 bias --taken at 14:35(by Annis??). Sp1 saturated. 6566 bias afternoon checkout. looks okay 6567 bias more checkout. looks okay 6568 bias " " " " TAPES: ====== none MIRRORS: ======== PRIMARY: -------- MIGS Axial A= 1.9299 Axial B= 0.5584 Axial C= 0.5554 Transverse D= 0.3939 Lateral E= 1.9144 Lateral F= 0.4160 GALILS Commanded: 5150., -2950., 400., -5850., 14600., 14100. 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: -1900 Temp: 6.1 C Altitude: 43.3deg MIGS Axial A= 1.9390 Axial B= 2.0460 Axial C= 1.9939 Transverse D= 0.1650 GALILS Commanded: -2568600., -2607200., -2536600., -5450., -10650. Actual: -2568484., -2606953., -2536541., -5450., -10650. SETMIR VALUES secDesOrient: -2040.60, -20.00, -8.00, 50.00, 70.96 secOrient: -2040.48, -20.00, -8.02, 50.24, 70.99 FOCUS LOG: ========== M1 Piston M2 Piston Temp Wind Time Inst setmir TCC setmir Az Alt C Dir MPH filt FWHM LN2 SCHEDULE: ============= Spectros filled at 06:00. Weight 111 lb. Imager dewar weight at 06:00 90 lb. WEATHER DATA: ============= Wind Time Temp F Dewp F MPH Direction Dust DIMM Sky Precip. ---- ----- ----- -------------- ---- ---- --- ------ 16:01 66 38 7 265 (W) 1072 - mclear none 17:01 66 40 0 244 (WSW) 1206 - mclear none 18:01 53 40 9 82 (E) 1242 - mclear none 19:01 48 39 22 75 (ENE) 1315 - mclear none 20:01 45 38 21 73 (ENE) 973 4.0 mclear none 21:01 44 38 19 77 (ENE) 1372 3.8 mclear none 22:01 44 38 17 73 (ENE) 1505 3.5 mclear none 23:01 44 37 12 81 (E) 1434 3.5 mclear none 00:01 48 37 4 114 (ESE) 1509 4.0 mclear none 01:01 53 37 11 182 (S) 1758 2.5 mclear none 02:01 53 38 10 177 (S) 2224 2.0 mclear none 03:01 51 37 9 180 (S) 1993 2.0 mclear none 04:01 52 37 6 184 (S) 2039 - mcl none 05:01 51 37 5 179 (S) 2446 - pcl none 06:01 52 37 15 177 (S) 2953 - pcl none 07:01 50 38 12 178 (S) 3678 - mclear none [pmt]cl = partly, mostly, totally cloudy PROBLEMS: ========= MCP: --- We had several instances of spontaneous rotator aborts through the night. It took more than one axis init to clear them. The rotator was between 150 and 300 degrees when they occurred, and in most of the cases, we know we were tracking, not slewing. At one point, we got aborts consistently at a rotator angle of 151deg 30min when trying to move the rotator to smaller angles. The rotator would move to higher angles. It was acting like a wrap angle problem, except that earlier in the evening, we had been able to move to the lower angles under the same conditions. ???? Finally after rebooting the MCP and going to 360 degrees to refiducialize (we couldn't go to zero without an abort...) we were able to cross 151 deg going to smaller angles. Go figure, Robert. None of the aborts show up in the watcher. RUNLOGS: ========