Subject: 2.5m obslog 20080218 (MJD 54515)
Date: Tue, 19 Feb 2008 05:22:41 -0700 (MST)
From: snedden@apo.nmsu.edu (Steph Snedden)
                       APACHE POINT OBSERVATORY SDSS 2.5M
                                 OBSERVING LOG
                            Monday February 18, 2008
                                  (MJD 54515)
---=== OBSERVING TEAM ===---
Elena Malanushenko
Steph Snedden
swatters (afternoon)
Jon Brinkmann - support
---=== OBSERVING PLAN ===---
        BrightTimeScience!
---=== OBSERVING SUMMARY ===---
Spent the night battling clouds and Moon. We took a lot of spectro exposures
with red Son-of-Spectro sky values. Hopefully, some of the SEGUE bright
exposures will be useful. We will ask for one plate that we think is done to
be replugged, and will ask for feedback on another.
Note to the observers: The plate database has been updated with old plates
that fill the void during first half and need to be re-observed. These are
Legacy plates and have higher priority than SEGUE plates right now. Please
have them plugged when the Moon permits it. Two first-half SEGUE bright plates
that can be re-observed have also been added to the database.
Jon resolved the ad2 problem during the early evening.
---=== OBSERVING LOG ===---
Afternoon:
---------
All systems checked.  The imager is still down because of last nights ad2
problem.
The MIG values are horribly off so we homed and relaxed both M1 and M2.
Spectro focus set for ~0.3C
Night:
-----
Jon found a large-ish lint ball in the power supply to the astrometric disk
drives and re-checked the connectors. After all that, ad2's pool disk came
back up properly. A bias was run and looked normal. Problem solved, we
sincerely hope.
01:34Z - Cartridge 4, plate 2939 - SEGUE bright
FK5 needed to find the field. Clouds and seeing were variable. Seeing ranged
between 1.5 - 2.0 asec at the beginning. All of tonight's data show red sky
values in SoS, but we continued to take exposures since these frames can
potentially be useful for sky calibration studies.
   This plate has previous signal from the dark run plus a plethora of moony
observations, so we think it is done.  However, since the next two nights are
engineering, we don't need it to be replugged tomorrow. This will give Brian
more time to respond with the pipeline results. Tonight we took a total of
9600s worth of moony exposures, the last two of which were taken under lower
efficiency conditions, and won't add much to the S/N, but may be good for the
sky calibration study.
05:41Z - Cartridge 7, plate 2893 - SEGUE Bright
GSOGTF, but efficiency less than 20 percent, so we waited for thinner clouds.
06:35Z - The clouds thinned out enough that we started observations. Used a
total exposure time of 5700 s, but high sky values and low S/N (all  Focus set ~0.3C (same as last night)