Thanks. Mine was set to the default 600, but that also seems to have not aborted the extra long solve attempt illustrated above. I've set it to 60 now, and I'll leave logging turned on in case it happens again. It's pretty rare... maybe once a month it feels like.

We have 2 threads in one here. As the OP is there a way to separate them? The original issue still remains a problem.

Is there documentation fof the parameters above?

Hi Dan

Did you try the source extraction method 'Internal SEP' together with Solving Method 'Local Astrometry'? I'm getting best and fastest results with this combination. (However you have to download all the required index files.) BTW, did you activate and update 'Use Scale' & 'Auto Update' and 'Use Position' & 'Auto Update' in 'Scale & Position' of the solver options?

Which 'Solver Profiles' do you use / did you try?

Concerning ASTAP, I used to run 'astap' directly (standalone) for better insights. (I have to remark, that ASTAP failed always with focal distances > 2700mm!)

Thank you. We had company and am now waiting for clear skys. Friday night is looking good. I will try these.

I have the same problem. Last week I updated my Pi, (Stellarmate) and plate solving become imposible. I run everything on the Pi, and never had any problem before.
I tried all the different methods, but nothing worked. Quite frustrating...

The only thing that was updated was default Align profile. It's not set to "Default" instead of "Small". Changing align profile makes any difference?

I did set it back to small and we had clear skys last night; the results were much better.
I am still looking for the astap logs. Offline experimenting with astap indicate it needs on the order to 100 stars to solve. A few of the test cases had less than that and they failed. All the cases with 100 plus worked. When it fails it would sure help to have the log.

Thanks Jasem, I will check this out at the next clear night.

Ok if it is confirmed by more users, we might need to revert to small scale even though "Default" should cover most cases.

I can confirm this problem but would even consider it being a bug.
I lost one night as I was not able to narrow it down the problem after I triggered the update function and the Align process stopped to work reliably and I was not aware of this post. I could use a number of clear nights (first time this year we have some in a row) to check. Setting the Align profile back to Small Scale in the options switched it back to rock solid autonomous operation.

Why I consider it a bug and not just a matter that "Default" should cover most cases:
1. Platesolve worked for me with no problem for polar alignment where the profile was "Default" and not "Small Scale" as well at the same time with the same setup, same exposure time etc.
2. First solving in the Align tab always worked. After this it reportet "not enough stars" and switched to blind solve. Only here and there the solver worked and I could not get to the target. Clearing the mount model did not help. After one successful solving the next attempts did not succeed (or very rarely every 7-8 attempts, automated scripts already stopped before)
3. Quitting kstars and starting the app again led to the same effect: again for the first plate solving in the align tab worked, the rest failed

The fact that it works once with the setting default is for me an indication that it is not just a matter of the general setting "Default" or "Small Scale" for the Align Process. Maybe I'm wrong, but I could recreate that behavoious with my equipment.

Hope this is helpful.

One wish from my side: If a parameter in the options that exists before is actively being changed by an update, could we make this transparent as part of the update procedure (Changelog text file?) or instead recommend users to switch rather than just doing it? This would give back a bit control. Assuming best intention to "improve" things, as a user I feel rather blind to sort out what could possibly be wrong when something that never grabbed my attention suddenly faiis.

Thank you for the report. To recap:

1. Default solver: works once, then fails afterwards with the exact same settings. On restart, it behaves the same, solves once then fails for all subsequent attempts?
2. Small scale: works all the time.

Is there any way to reliably reproduce #1? Maybe share the images that failed to solve with #1 the 2nd time? I'll try then see what could be causing such behavior.