Resolved Guider Not Bumping Mount Consistently

New problem, alas.

The AO has started not bumping the mount. It's odd; the pointing still is close to perfect, and the tracking is close to perfect when the seeing is good, with very little change in tilt for entire images. So I don't believe that something has happened to the polar alignment. Principally, the problem seems to come up when an image starts, and Maxim lined up the guide star too far from centered, and/or when there is horrible seeing. A variant on that is that, when it takes four images in a row (one hour total imaging time), and the mount doesn't need recentering (not enough aggregate wander) between images, it can go beyond the set threshold after several images. But I see no sign of the mount ever being bumped when the AO gets past the settings, and it obviously should when the tilt gets past the set threshold.

I believe the settings are correct:
ASCOM Direct, using ASCOM Telescope Driver for TheSky (mount is a Bisque Paramount ME); I am not aware of any changes made to setting which might have caused this. It's set to bump when the tilt is more than 75 or less than 25. "Bump time" is set for .15 sec.

The mount moves when I hit the "Bump" button, when it's not guiding (button grayed out when guiding). Maxim guides just fine when I'm not using the AO-X (camera is an SBIG STX-16803 with an STX Guider). Obviously, Maxim is able to control the mount.

Maxim will calibrate the mount, using both the camera control/guide tab (if SBIG Universal is selected as the camera), or the AO tab (if SBIG w/AO is selected as the camera). The AO clearly is well-calibrated.

Sometimes "ASCOM Direct" is grayed out while guiding; sometimes not. I don't see a correlation between this and when it's not bumping the mount.

This problem happens whether I'm controlling things with ACP, or using Maxim stand-alone.

I've been imaging with various SBIG AO devices since 2002, and I've never seen this happen before.

 

It is the same, except I updated this post as I learned more.

Any ideas what could be happening?

 

Ok, I'll increase the bump time.

I have attached a screen shot of the settings.

 

Well, there's good news, and there's bad news.

The first good news is that increasing the bump time may have solved the bump problem. The need for a bump seems mostly to result from the dither ACP puts at the start of each image; this is especially an issue if Maxim didn't properly center the guide star in the little box, or if the tilt is significant left over from the previous image (Maxim does not seem to automatically revert to 50% AO tilt to start each image). At 2 second bump time, Maxim just played ping-pong with itself, sending the guide star corner to corner, probably because it was over-correcting. At .5 second bump time, it didn't seem to be enough. I tried 1 second, and that seemed to work ok, but perhaps was a bit long. So I now have it set at .9 second, which seems to be working fine. Time will tell.

The bad news is that Maxim really does not want to keep the guide chip binned at 3. When the system opened, it was unbinned, which kills the system (I'm guessing it has to do with ACP's guided dither to start each image; it seemed to think that the actual photo taken of the unbinned guide chip was too big). Then trying to coax it into binning 3x3 caused a cascading series of failures, ending with me turning the camera and mount off, then back on, and rebooting the computer. Then it behaved. But this is still a problem, obviously. And, yes, if I set the binning at 3 in the AO box, then close Maxim, it generally comes back up that way. But obviously not always, since I had changed nothing since last time I imaged.

But more good news is that I haven't seen any sign of the 0.2Hz AO rate since I started binning the guide chip at 3x3.