APACHE POINT OBSERVATORY SDSS 2.5M OBSERVING LOG Friday January 9, 2004 (MJD 53014) ---=== OBSERVING TEAM ===--- Stephanie Snedden Howard (Mr. Fiducials) Brewington ---=== OBSERVING PLAN ===--- Standard pre-shakedown checks ---=== OBSERVING SUMMARY ===--- Spectro monthly checkout started. DIMM checked out. Fiducial crossings in azimuth look bad and will be checked again tomorrow. ---=== OBSERVING LOG ===--- Spectro Monthly Checkout: ------------------------- Original collimator actuator positions: sp1: sp2: ---- ---- A= 0 -31133 B= 0 10252 C= 0 6718 After positioning in x: A= 600 -31133 B= 600 10252 C= -601 6718 After positioning in lambda: A= 100 -30130 B= 1100 9258 C= -601 6718 After focus: A= 1948 -28351 B= 2948 11037 C= 1248 8499 Dithered flats: frames 24574-24580 contained the dithered flats; frames 24581-24582 the arcs. Biases and darks will be taken tomorrow night. Fiducial Tables: ---------------- The azimuth fiducial crossing data that Wendell generated was incomplete. Most fiducials were missing data for two crossings. Although we suspect this is a "getclock" problem, we could not find the relevant data on the MJD it was taken, nor on the previous or later MJD. Howard wound up retaking the azimuth crossing data. The new data looked very bad, with large jumps in the errors. I will try taking more data tomorrow at warmer temperatures, and keep an eye on the drive currents as the telescope moves in azimuth. Needless to say, we did not check in new azimuth tables. The tables for the rotator and altitude were not significantly different than the tables already checked in, so we made no changes there, either. DIMM: ----- Checked the following: Glass wedge: The wedge was solid in its housing, but the housing was loose on the aperture cover. It was tightened down. The apertures were then roughly aligned. I will fine tune the alignment tomorrow and place alignment marks on the telescope tube and aperture cover. Focus: Focus was quite a bit off. The focus was adjusted (approx. one full turn clockwise was needed). Plate scale: I *think* I found the problem with the plate scale. I put in a scale in pix/arcsec when it should be arcsec/pix. Oops. The final check will be when we can compare the DIMM to the 3.5m and 2.5m. Centering routine: The centering routine made proper adjustments tonight, although the images tended to stay N of the chip center by about 1/4 the width of the chip. I am not sure what caused the problems that other observers have noted. The only thing that may be different is that I forced the DIMM software to make a centering correction at the beginning of the night, then clicked the auto-centering button. Note that the pressure to the tub lid is too low, and I had trouble opening the lid. The last time this happened, it was very cold, but tonight the problem happened at T=+2 C. The small monitor at the telescope looked fine tonight. It is likely that the interleaving problem we saw previously was caused by cold temperatures. Other stuff: ------------ The tape drives were given their monthly cleaning. The guider focus was checked and adjusted on cartridge 2. Spectro summary: =============== 03:43 24569 2.1 arc monthly checkout 03:53 24570 2.1 arc 03:56 24571 2.1 arc 04:10 24572 2.1 arc 04:12 24573 2.1 arc 06:38 24574 10.0 flat 06:42 24575 10.0 flat 06:46 24576 10.0 flat 06:50 24577 10.0 flat 06:54 24578 10.0 flat 06:58 24579 10.0 flat 07:02 24580 10.0 flat 07:06 24581 2.0 arc 07:09 24582 2.0 arc ---=== WEATHER LOG ===--- Wind Time Temp F Dewp F MPH Direction Dust DIMM Sky 03:44Z 38 -7 11 121 (ESE) 146 - 04:16Z 38 -7 13 110 (ESE) 0 - 04:48Z 35 -1 12 103 (ESE) 0 - 05:21Z 35 4 10 99 (E) 0 - 05:53Z 34 5 10 96 (E) 0 - 06:25Z 34 5 11 86 (E) 0 - 06:58Z 34 5 9 111 (ESE) 0 - ---=== TELESCOPE STATUS ===--- Stowed at 30 deg. alt with cartridge 2 mounted. Spectro auto-fill connected. ---=== SOFTWARE USED ===--- IOP/SOP: v3_124_0 Watcher: v2_24_0 MCP: v5_24_0 TPM: tpm_v2_36_0 AstroDa: v14_47 TCC: 0 sdssProcedures: v1_82 SoS: v4_10_7 hoggPT: v1_6_9 plate-mapper: v4_3_1