On Fri, May 16, 2025 at 01:12 PM, Gabriel Wiklund wrote:
sometimes after a GoTo/Slew/Recenter the scope slews away as if the backlash has not been cleared
I get that too, from time to time, even with an ArgoNavis.? I have reason to believe it's just a timing issue with ServoCAT talking to the DSCs.? ArgoNavis gives beeps indicating when the slew is "done", after ServoCAT having done the talking to the DSCs thing and recentering.? ServoCAT still moves along with that beep from time to time, and less often, after the beep.? Highly intermittent, and I have found nothing making it more likely than not to happen.? On one night, and one night only, I had it happen a few times, so I unplugged and re-plugged the serial connections on the SC and the AN, and it went away.? That's not enough to say it's related, but maybe perhaps?
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That this doesn't happen with slews, but only with gotos, is what makes me believe it's a timing issues.? With a slew, there is no talking to the DSCs for refinement.? You could try just letting PHD2 take care of it, which only slews rather than sending gotos, but the issue is that with PHD2 and alt/az, you need to recalibrate every so often as the parallactic angles changes - the camera chips are rotating relative to the sky as the scope tracks.
