Never ending loop

[giraud]

Hello Robin,

Sharpcap entered into a never ending loop during an imaging sequence. Last image was taken at 23:06.
Please see attached.

Cheers,
Eric

PS: I would suggest to augment the max log size on the forum as I had to cut quite some log to make it fit under 1Mo

[admin]

Hi Eric,

what I can see in that log are an awful lot of PHD2 StarLost messages. Since the sequence has 'Require Guiding' set to on for the capture step, SharpCap cancels any frame being captured if the guiding is lost while capturing (exception : if the frame is more than 95% complete).

PHD is losing lock every 3 to 6 minutes in the log on average, so with an exposure of 600s set, frames do not complete and the sequence keeps retrying to capture the frame again.

Oddly PHD seems to recover again fairly quickly after each star lost event - can't really tell from the SharpCap log what was going on in PHD2 to cause this to happen, even from the PHD2 log there may not be enough info. Perhaps the occasional cloud?

You can obviously set 'Require guiding' to off to avoid this issue - SharpCap will then allow the frames to continue even if PHD2 reports that guiding is lost. The behaviour you are seeing is pretty much what is supposed to happen if 'require guiding' is turned on and the guiding drops, although I will consider whether I should allow for a small amount of missing guiding before cancelling the frame.

cheers,

Robin

[giraud]

Thanks Robin,

I suspect there is a sporadic link issue between PHD2 and Sharpcap.

Tonight I got the message "guiding lost" (that lead to the en of the sequence), while the guiding was doing very fine in PHD2 at the time of the event and even the minutes before.
I attach the log (see 21:58:22.810991).

The PHD2 Shapcap settings in "the "Guiding tab" are "Host Name: Local Host" and "Port: 4400" and "enable server" is hooked in the PHD2 app. Anyting else I should check?

I have just included the "Capture X frames (guiding required : True)" inside an "Ignore erros while running these steps" hoping guiding error message will not kill my night sequences. It prevented Sharpcap to exit the sequence too early in the night, but it still lead to an early termination as several of the timing loops were consummed without imaging.
My .scs sequence is attached.


Cheers,
Eric

[admin]

Hi Eric,

unfortunately the 'Ignore Errors' will not help here, since the loss of guiding isn't considered an error, it's considered to be something that needs to be dealt with (by asking PHD to restart and then re-capturing the frame).

Looking at your SCS file, I can see that you have 'Guiding Connect' steps scattered through it - that should be unnecessary and is certainly not something I designed for - I would expect just one of those steps ('Monitor Guiding Application' in the UI) at the start of the sequence. I wonder if that is part of the problem? The step is not designed to deal with the case where guiding is already connected, so may be adding to your issues.

In the log, I see 3 'LostLock' events, all between 21:08 and 21:09 - these are occuring during a focus scan, which might explain why PHD2 loses the lock at that point. While the scan is running, the sequencer won't be worrying about the lost lock status, so that will not have been relevant in the latest test.

So, I would suggest cutting back the 'Monitor Guiding Application' steps to a single one at the start. If you still see 'lostlock' events in the SharpCap log, check the PHD2 log for the same time to see what it recorded.

cheers,

Robin