Tom, how does the autoguider calibration look compared to before? Does it take RA and/or DEC more time to reverse direction? If dithering takes a lot longer now, I start suspecting increased backlash (due to worm/gear mesh being too loose) or, alternatively, some stiction which is the result of a tight worm mesh.
?
If you run a calibration, and then record some autoguiding logs, it may help to post them here for others to take a look. It may show when and why some of the large RA jumps appear.
?
Regards,
?
? -Paul
?
On Tue, Jan 28, 2025 at 05:26 PM, Thomas Kallenbach wrote:
John and Paul,
Thank you for the replies.? Apparently I don't have notifications enabled so I just saw your messages.
My balance is good and I do a new polar alignment and calibration every night because it only takes a few minutes.? This problem has been happening for several months now, but we have had clouds for two months so I hasn't been a big deal.? Two months ago, I tightened all the screws and waited for a clear night to try it out.??
I thought about taking both extensions off and trying it again but that seems like a lot of work.? I am using one , 21 lb (I think it is) CW located about halfway up the shaft.? I think I tried using the 7 lb and 21 lb closer to the mount to reduce the moment but as I recall, they were too heavy even close to the mount.?
In the past I balanced the scope without regard for it being east-heavy.? Last night I adjusted the CW slightly so that it would be east-heavy.? No difference.? The DEC runs around .3-.7 by the RA is all over the place.? Sometimes it will be very good, then all of a sudden it spikes above the x-axis.? Then it spikes below the x-axis.? Dithering used to take very little time but now it takes a long time to return to stable guiding.??
Paul, how would the worm gear have been affected?? What should I check?
Tom
Paul Kanevsky