Date: Tue, 29 Feb 2000 08:12:45 -0700 From: "s. a. snedden" Subject: 2.5-meter Obs Log (MJD 51603) MONDAY FEBRUARY 28, 2000 (MJD 51603) APACHE POINT OBSERVATORY SDSS 2.5m OBSERVING LOG Observing team: Ellyne Kinney (early) (APO) -- PIC Jeffrey Hayes (early) (APO) Steph Snedden (late) (APO) Atsuko Kleinman (late) (APO) Bing Chen -- PT (JHU) Visitors: Scott Burles (FNAL) David Schegel (PU) Connie Rockosi (UC) Jim Gunn (PU) The plan: We will continue our spectroscopic commissioning if the weather permits, and after midnight or 02:00, change over to imaging so we can experiment with and commission the end-to-end DA. Results: Dust and wind gusts kept us closed until about 02:00. We eventually did some imaging parked on the equator, but seeing was quite bad (2.0 arcsec to 2.5 arcsec on DIMM, but more like 3 arcsec on our images), so nothing was really done with the data. The rotator could not be fine tuned enough because of the bad seeing. Connie spent the afternoon/evening working on U2 again. RHL worked on more aspects of the MCP this afternoon. We loaded cartridge 3/plate 267 for the opening moves this evening (assuming we can open). Scott and David persisted in trying to find the spectrograph light leak. At 17:30 we started the TPM logging. Scott, David, and Connie played around with tracking down the light leak in the spectrographs and they think they know where the source is -- there will be a more complete report separately. This was done by 21:30. At 21:45, it was reported that Dan Long was ill, and so could not make it in tonight. Atsuko came in to cover. We removed the cartridge and corrector, and installed the imager at 00:45, still inside the building. After installation and swapping empty LN2 dewars, we decided the wind had dropped enough for us to open. The building would not move at first (see problem 1 below), however, finally we were open with fiducials set at 02:30. At this point we noticed the blowers were not on (see problem 2). We then proceeded to begin an on-equatorial parked drift scan. Focus ranged from 1800 to 1300 as the mirror cooled, over about 3 hours. Interlocks: None bypassed. LN2: Spectrographs were filled at 16:00. The imager dewar was replaced at 02:00. The spectrographs were topped off at 02:00 and 06:30. Weather: Clear to partly cloudy with very high winds and dust at 17:30. Wind advisory through 21:00 this evening. At 22:30 the wind was 36.6 mph, and over our closure limits. At 23:30 the wind gusts were hovering around 35 mph, and we stayed closed. At 00:30 wind gusts decreased to around 30 mph. Humidity varied from 20%-50%. Wind started from out of the west, but gradually shifted so that by 02:00 it was out of the north. DIMM seeing bounced around between 2 and 2.5 arcsec. Dust peaked at almost 1700 particles/ft^3 at 20:00, then dropped to 50-70 particles/ft^3 after midnight. Tapes: We ran endNight for the practice, but do not intend to ship the tapes. The tapes were removed and put in the designated recycling box in the tape cabinet. Fresh tapes were put in the drives. Telescope: The telescope was left at 30 deg. altitude with the imager on. Cartridge 3 plus the corrector were left on the cart in the enclosure for re-installation, if desired. ------------------------------ MIRRORS PRIMARY: MIGS Axial A=1.9314 Axial B=0.5564 Axial C=0.5564 Transverse D=0.4034 Lateral E=1.9804 Lateral F=0.4724 GALILS Commanded: 000032750, 000025550, 000028000, -000009500, 000000150, 000 000 Actual:000032750, 000025550, 000028000, -000009500, 000000150, 000000000 SECONDARY: Focus:1350 Temp: 25 deg F Altitude: 57.22 degrees MIGS Axial A=-1.1699 Axial B=-1.1250 Axial C=-1.1419 Transverse D=0.0559 GALILS Commanded:001395050, 001382200, 001371900, -000000750, -000005350 Actual:001395152, 001382308, 001372109, -000000750, -000005350 ------------------------------------ PROBLEMS: 1) The building refused to move at first, again. It gave an oveload (OL) message. CLR WRT fixed the problem. This is the second time this has happened in the last month...the problem is definitely increasing in frequency. 2) The lower enclosure blower would not start tonight. The LED below the switch stayed off. The green LED on the panel door stayed on. Atsuko remembers it going off and the red LED on the door blinking when the blower is in operation. We tried power cycling and checking circuit breakers, but we were not able to get the blower to start. In the morning, Larry C. and Steph had another look. We were able to open and close the baffle, but the fan would not start. It turns out that when we had the HVAC switch in the correct (middle) position, we simply did not wait long enough for the fan to kick in when its switch was turned on. It's a good thing we dealt with this on a night of lousy seeing.