Mach2 RA Judder

Brent Boshart

An issue with my RA axis has developed with my Mach 2.  Everything starts off fine and then I begin to notice egg shaped stars across my whole image and are elongated in the same direction as RA.  It does not matter if I expose for 2 secs or 30 secs, the shape is the same.  Tonight I was imaging saturn and the same issue suddenly started.  In the video below you can see saturn juddering back and forth while the mount is sidereal tracking.  The last few seconds in the video, I slew in RA at 1x and you can see it smoothen out.  I am not using tracking correction in APCC, in fact if I don't use APCC and the ASCOM driver only I get the same results.  Counterweights and shaft are tight. I have an AP 18lb weight near the top of the shaft and a 10lb weight about halfway down. The issue is happening frequently but is intermittent.

Join to automatically receive all group messages.