Yesterday we noticed that the Allsky camera CCD temperature was listed as 0 deg C. That might happen if the night is particularly warm (say 20-25 deg C) but that wasn’t the case. We waited for the camera to power up Tuesday evening (it is on a mechanical timer to shut it off in the daylight as it has no iris to protect it from excess light) and checked the peltier cooler temperature setting in the software and it was indeed set to 0. Arrg. why? Changed it back to -40 so that it would always seek its coldest temperature and all went well.
Here are two comparison images, just one exposure apart showing the difference in image quality with a warm vs a cooled CCD chip.

warm ccd

cooled ccd