I had a multiple jobs schedule last night. All lights jobs have Track, Align, Focus, and Guide boxes checked. Scheduler runs a few jobs successfully. Then next unlucky job slews to target and hangs right on initiating focus. I have not touched anything on UI by this point yet. I noticed the problem and hit just the Auto Focus button manually. It ran the focus, then Scheduler picks up from there and continues just fine.
The exact same thing happened twice: 18:49:44 and 20:05:41.

I took a look at your log file. In both cases "Discarding Autofocus start request - AdjustFocus in progress." seems to be the reason.

That means that adjusting the focus position was ongoing when the autofocus should start. I'm not so sure whether this discard really makes sense. But I'm not an expert on focus. I'll post it on our development group...

Thanks for the logs Konstantin, I think this is a bug in Focus. I'll work on it later today.

Btw, I have nonzero filter offset configured for my B filter only.

Thx, would you be able to post a screenshot of your Filter Settings popup please?

We know specifically what the bug is, but are still trying to piece together the series of events that trigger the bug.

I'd like to chip in a possibly related case.

I also have filter offsets configured and none of the filters have the "autofocus" checkbox checked.

The other day I was dealing with the filter wheel issue where it was rotating in both directions and failing to position precisely (backlash).
To analyze the issue and fix it I only really needed the camera and the filter wheel, so I created a new Ekos profile without anything else.

Shooting through filters was impossible in the Capture module, because it would hang on filter change.

I realized it was probably trying to apply offsets without having a focuser connected, added a focuser simulator to the profile, and it all started working fine.

I guess there must be an assumption in the code that the focuser is available, and it could be beneficial to just add a verification before actually using it.

I am out of home for the next three weeks.
I have zero offsets for everything but B. All filters locked to G for AF. Adaptive start position is enabled and temperature compensation coefficients are set for all filters to the same value.

Thanks Konstantin, do you autofocus when you image G which triggers an autofocus, or are you autofocusing every 30mins or some other way?

What's happening is that a filter change to or from B is triggering a focuser move of 24 ticks which, with the 300 ticks Overscan you have set, creates a 324 tick out move following by 300 in. This takes a few seconds to complete but its just long enough to cause a conflict with the next autofocus. Its this conflict that causes the scheduler to hang. I've got a fix for the scheduler hang (I think) but we're trying to exactly understand the circumstances that cause the problem, and we haven't quite got there yet.

Thanks Kiril, I expect you're right, when you swap filters, capture will wait for the focuser to confirm its moved by the appropriate offset. The other way around this, other than adding the focus simulator, would be to set the offsets to zero so no focuser movement is required. Its obviously problematic where some setup expects a focuser (offsets) and some setup doesn't have it (optical train).

BTW, I think some filter wheels allow the user to specify an option to approach filters from 1 direction only to avoid the situation where backlash prevents the filter from seating properly in the slot. I've not used this myself but thought it might be of help.

I set 'locked to G' in AF filter settings, so that it runs AF with G filter no matter what is the Capture's current filter.
I run AF at the beginning of each job, every N (usually 30) minutes, and when temperature drifts 0.7°C. The last two effectively randomize what would be in the filter wheel right before AF starts.
Yes, I do have AF Overscan too.

Hi Konstantin,

I've merged a fix for this. It will be in 3.6.8 which is about to be released.

I can't reproduce exactly your issue from the scheduler, but I can reproduce the issue in debug so I'm fairly confident my fix will resolve this. If not and you get a repeat of the issue just let me know and I'll have another look.

Regards,
John.