Hy Murveit replied to the topic 'Internal guider questions' in the forum. 3 years ago

Sorry Magnus, not much to say. 

I assume you're using PHD2 through KStars/Indi, so they're using the same Indi mount drivers.

I will note that as I understand it, the PHD2 folks recommend calibrating once and leaving it, e.g. not recalibrating for months, unless you change the guiding imaging setup (e.g. rotate the guide camera, remove it, or something like that).  I have taken that to heart, and I personally don't calibrate often either. As you probably know, the internal guider has options to keep use the calibration--e.g. do it once where it works nicely, e.g. near the meridian and the equator, and keep that calibration for a long while instead of recalibrating on every slew.

The calibration scheme simply pulses the mount the amount specified, e.g. 1000ms, every step it takes, without regard for the guide rate, until it sees enough movement. Is it possible you have a lot of backlash, and somehow PHD2 compensates for that better than Ekos? I guess you can measure that with the PHD2 guiding assistant.

Do you have these issues in both RA and DEC?

BTW, now that I think of it, it's also possible that the issue is star detection, not mount movement (e.g. the issue could be improved with improved stellarsolver parameters for guiding).  That would be obvious in a log with debugging enabled for guide and fits.

Hy
 

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