SARA 

William Keel

University of Alabama

3 cats

FLI CCD

8.5

0

No problems to report

Test drive, galaxies in H-alpha. Focus=133000. Even after initialization, the guider x-stage has limited movement; to the west it can’t quite reach W1. The NSEW directions are 180 degrees rotated from their previous directions; +x is to the east and +y to the north. The guider settings for x and y speed and angle are 1,1,0 (sign changes on the speeds from previous values). The guider focus is close to 0. Guiding works well; in some parts of the sky there were oscillations of 1-2” lasting several minutes, as if the slow-motion controls didn’t have enough authority in those locations. There was one complete guide failure where the stars wandered around by 30 arcseconds. Evening twilight flats showed a very large elliptical “Eye of Sauron” pattern which is new; bright in some filters and dark in others. There are also three new narrow features looking almost like scratches. I’ll check in the morning to see how reproducible these flat-field features are and compare sensitivities using Landolt standards with the latest pre-shutdown values. The cooler is struggling even with set point -30 C - the reported value ranged from -22 to -28.

Xianming Han

Butler University

none

CCD

7

1.5

Software/Control PC Issues

Observed eclipsing binary. 1. The ACE control cabinet needed rebooting at the beginning of the night. 2. The FWHM was spreading too widely for the same focus position, so that the auto focusing was confused about what is the best focus position. Solution: narrow down the search range. 3. Telescope lost tracking about 2 hours before the end of the night. Once that was fixed, the dome lost tracking It turns out the dome does not move at all, not even manually. So closed the telescope.