AP Meridian flip misbehaviour - Tracking Stops at Meridian

[Tom Richards]

Hi Bob
Sometimes tracking stops during the last image before meridian flip; the trailed image cannot be solved so after flip there is no pointing correction (except for the initial auto-center).
Details: Exptime 15s, no filter change. Flip settings - mount can track 10m past, needs 2m assurance. Log: entry says waiting 117 sec to pass flip limit (that log entry is after the trailed image is downloaded). Equipment, A-P 1200 GTO.
This failure happens only sometimes, even with the same 15s exptime.
Solution would be appreciated! Thanks.

[Bob Denny]

So your AP 1200 will not track through the meridian? That would be strange. Or maybe you have a "meridian delay" cheat set up where it flips late? Or some tracking limits set up in the mount? I am not an AP expert, maybe someone can chime in here?

One thing that might help is a log file from the run.
Attach it here to your reply (don't paste) <-- link to attaching instructions

[Ray Gralak]

Hi Tom,

Hi Bob
Sometimes tracking stops during the last image before meridian flip; the trailed image cannot be solved so after flip there is no pointing correction (except for the initial auto-center).
Details: Exptime 15s, no filter change. Flip settings - mount can track 10m past, needs 2m assurance. Log: entry says waiting 117 sec to pass flip limit (that log entry is after the trailed image is downloaded). Equipment, A-P 1200 GTO.
This failure happens only sometimes, even with the same 15s exptime.
Solution would be appreciated! Thanks.

Are you running APCC? If so do you have meridian limits enabled? If so, that might be what is causing tracking to stop.

-Ray

[Bob Denny]

Thanks for chiming in Ray! I appreciate your help.

[Ray Gralak]

Hi Bob,

I don't always get a chance to look at every post so feel free to "ping me" via private email if an AP related topic comes up!

Best regards,

-Ray

[Bob Denny]

OK, thanks. I totally understand, I can't keep up with the support tickets on all of the equipment we work with either :-)

[Tom Richards]

Hi Bob and Ray
Thanks for replies, and apologies for my delay in getting back - I've been away.
No I'm not running APCC, nor have I set up a meridian flip cheat. I'm attaching the log - search for 'flipping'.

[Ray Gralak]

Hi Tom,

Hi Bob and Ray
Thanks for replies, and apologies for my delay in getting back - I've been away.
No I'm not running APCC, nor have I set up a meridian flip cheat. I'm attaching the log - search for 'flipping'.

I don't see anything in the logs that suggests that tracking was stopped, but I can't be sure without the AP V2 ASCOM driver logs.

However, if you have trailed stars is it possible that the mount's clutch is slipping? That might happen if the clutch is loose enough that a weight imbalance or caught cable might exert enough force to cause a slight amount of clutch slippage and thus cause trailing.

-Ray

[Tom Richards]

Hi Ray and Bob, Ray's post set me looking at the A-P driver log. That held the clue. It was turning off tracking when the scope reached the meridian. So I reset it to turn off tracking 10m past the meridian, to agree with the ACP "can flip" setting. Tests all showed the problem had disappeared, so here's hoping! Thank you both.

[Bob Denny]

How do you turn off tracking at the meridian? So if you are just rolling along imaging, with the scope tracking, it "just stops" at the meridian? That's mildly surprising to me.