From: "N.C. Hastings" Subject: 3.5m Night Log 990618 Date: Sat, 19 Jun 1999 03:14:57 -0600 Apache Point Observatory, Sunspot, NM Friday, June 18th, 1999 3.5-meter Night Observing Log Actual ---------------------------------------------------------------------- ASTRONOMER OBSERVER(S) INSTRUMENT DATE START FINISH ---------------------------------------------------------------------- P.Szkody P.Szkody Echelle 6/18-19 --:-- --:-- J.Brown J.Brown Echelle 6/19 --:-- --:-- ---------------------------------------------------------------------- INST SCHEDULED WEATH EQUIP OBS DAY NOTUSED I/RS/DN START FINISH D B D B D B USE D B ---------------------------------------------------------------------- UW05/R 21:56 01:10 2.6 0.7 0 0 0 0 0 0 0 WS01/R 01:10 04:13 3.1 - 0 - 0 - 0 0 - -------------- Activity Log -------------- Observing Specialist: N.C.Hastings The telescope remained closed due to thunderstorms. We did spend some time discussing echelle aperture issues. It seems that the 1.6"x1.6" square aperture cannot be flat fielded sufficiently to reduce the data taken with it. The 1.6"x3" slit can allow bad seeing or poor guiding to reduce the order separation to less than a pixel, or around a pixel, which makes it difficult to subtract sky. After much discussion, we (three program's observers) have decided to return to the rectangular aperture for now. Switching apertures is quite an issue for many reasons. For one, without the light baffling we have to tape the echelle up with gaffer tape and foam rubber to make it light tight. Every aperture switch requires removal of this light proofing. The second issue is that to loosen the screws for the apertures you must put an allen wrench directly amongst elements that have been painstakingly aligned by Shu-i. One slip of a wrench and we will need to re-align something. I think this is an issue that requires more attention as soon as possible, or agreement on a standard slit. FOCUS LOG June 18th 1999 Best Telescope Temp Wind Seeing Time Instrmnt Focus Az El Air/Truss Dir MPH filter FWHM" --------------------------------------------------------------------- WEATHER LOG June 18th 1999 Wind Time Temp-F Dewp-F MPH Direction Dust Sky Precip ------------------------------------------------------------------ 16:01 56 45 6 97 (E) 987 Cloudy None 17:01 53 41 11 86 (E) 719 Cloudy None 18:01 49 45 17 54 (NE) 694 Cloudy Rain 19:02 52 41 14 65 (ENE) 498 Cloudy None 20:02 55 36 10 77 (ENE) 354 Cloudy None 21:02 55 34 15 60 (ENE) 443 Cloudy None 22:02 54 38 11 77 (ENE) 666 Cloudy None 23:02 56 32 10 79 (ENE) 556 Cloudy None 00:02 55 34 16 74 (ENE) 567 Cloudy None 01:02 55 34 3 313 (NW) 528 Cloudy None 02:02 53 46 7 179 (S) 571 Cloudy None 03:02 50 46 10 148 (SSE) 448 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 for the particles > 1 micron per 0.1 cu.ft. TELESCOPE STATUS Primary, secondary, and tertiary mirrors in place and collimated. Primary support system operational. Mirror ventilation system in place. Telescope drives operational. Current Remark version: 2.5.5b5 Current guide software version: GIm Ctrl v3.0b23 - NCH