Subject: 3.5m Night Log 20090609 Date: Wed, 10 Jun 2009 14:08:06 +0000 (UTC) From: bketzeba@apo.nmsu.edu Apache Point Observatory 3.5m Telescope Night Log Tuesday, June 9, 2009 ACTUAL ASTRONOMER OBSERVER(S) INSTRUMENT START FINISH ------------------------------------------------------------------- M.Klaene B.Ketzeback Agile --:-- --:-- 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 21:13 04:51 0.8 6.8 0 0 0 0 0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- Observing Specialist: B.Ketzeback Unable to open tonight due to heavy cloud cover and local area showers. I spent the night working with Agile and the filter wheel. After taking a series of dome flats I discovered that the exposure times for the commanded filter positions did not make much sense. I was able to determine that the filter wheel software was moving the filter positions in the wrong direction and was improperly mapped so that the desired filter was 180 degrees from the actual filter in place. Fritz happened to be still logged on and working from home so he was able to correct this bug. I was able to determine exposure times for a dome flats for a number of filters. These exposure times result in signal levels in the 10-15% of saturation range. SDSS u - Bright Quartz Lamp - 90s SDSS g - Dim Quartz Lamp - 60s SDSS r - Dim Quartz Lamp - 15s SDSS i - DIM Quartz Lamp - 10s SDSS z - DIM Quartz Lamp - 10s Unfiltered - Dim Quartz Lamp - 5s MSSSO U - Bright Quartz Lamp - 90s MSSSO B - Bright Quartz Lamp - 5s MSSSO V - Dim Quartz Lamp - 40s MSSSO R - Dim Quartz Lamp - 15s MSSSO I - Dim Quartz Lamp - 8s The test flats that I took still have uneven illumination across the field of the chip. I spent much of the rest of the night attempting to understand the probably cause of vignetting or scattered light into the field. In some filters (and with no filter in place) there appears to be a significant gradient with increasing column numbers across the chip. In other filters, there appears to be a vignetted square pattern rotated -45 degrees to the chip. I verified that in these cases the filter was properly positioned and not stuck between desired locations. I also verified that there are none of the baffles that have been inproperly installed that would vignette the corners of the field. Further investigation needs to be done. I will attempt to rig up a pinhole later today to see if this will help trackdown scattered light. ------- FAILURE LOG ------- PROG INST FAILURE MODE TIME (SEDFNVOG) TI/SHU START FINISH DESCRIPTION ---------------------------------------------------------------------- ---------------- FOCUS LOG --------------- Time Instrument Focus Az El Temp Strc Prim Sec Air filt FWHM -------------------------------------------------------------------------- ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------- 16:00 54 35 5 252 (WSW) 356 ptly cldy none 17:00 54 36 10 327 (NNW) 418 mstly clr none 18:00 60 37 10 308 (NW) 454 ptly cldy none 19:00 59 37 11 228 (SW) 434 ptly cldy none 20:00 55 36 7 262 (W) 464 cloudy rain 21:00 47 43 8 325 (NW) 741 ptly cldy humid 22:00 47 43 8 1 (N) 2303 cloudy none 23:00 49 38 10 3 (N) 3527 cloudy none 00:00 50 37 1 227 (SW) 860 cloudy none 01:00 47 39 8 25 (NNE) 787 cloudy none 02:00 51 37 3 170 (S) 703 cloudy none 03:00 51 37 6 183 (S) 683 cloudy none 04:00 52 37 11 190 (S) 695 cloudy lt rain 05:00 50 37 8 235 (SW) 667 cloudy none 06:00 50 38 10 226 (SW) 691 cloudy 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: 2.10.0