Imaging during EST to DST change over

Jim Fakatselis

Last night I was imaging with my QSI683 camera through the AP 130EDF on my Mach1GTO and had an unusual thing happen. I was on my last subframe of the evening, at around 2am and suddenly I noticed that the guiding errors grew tremendously.

I noticed the guide star was out of the field so I grabbed an additional full frame exposure through the guide camera to see what had happened. A 5 sec exposure showed stars streaking in the field of view, like the tracking was incorrect or even off.

After closer inspection I noticed that the mount parked itself at exactly 2:00am when the PC's clock automatically advanced from 2:00am to 3:00am during the EST to DST transition. It wasn't too much of a problem since I was closing down for the night anyway, so I lost the 10 min subframe.
I was wondering why/how the mount automatically parked due to that sudden time shift Any ideas? Anyone else had this happen to them?

Jim Fakatselis
Peppermill Skies Observatory
Huntington, NY

Join to automatically receive all group messages.