I have a question about guiding and guide calibration. So here’s my problem.
During an imaging session, I will go through guide calibration, start guiding and have a pretty good night (RMS - 0.5 to 0.7). On other nights I will use the exact same set-up, do a guide calibration again, only this time the dec and ra plot graphs will fly wildly off the chart and I have to stop the session as I can’t recover it. Sometimes this will happen during the same session if I slew to another target and do calibration again (should I be doing this?).
My set-up doesn’t change from night to night. My polar alignment is within 7 arc sec. My settings don’t change. My calibration pulse is set to 500. Not sure if this is the correct value but I read on this forum somewhere that’s the value I should use.
Can I re-use a previous nights calibration say from a week ago when I know everything was working? Should I be calibrating when I set-up again? Is the calibration plot meant to be orthogonal? The one last night wasn’t. It was straight up and down. What would cause this?
My mount is a SW AZEQ6GT. When it works I all works, I get really good guiding.
I did read on this forum to ensure my guide calibration has been done properly but it was never explained what “properly” was. So any advice would be appreciated.
Thanks in advance. I know there’s a lot to unpack but this is the last piece of the puzzle in getting my imaging sessions to run error free.
Can I re-use a previous nights calibration say from a week ago when I know everything was working?
No, In fact I will routinely toss calibration data between targets. the guider will try to use previous position and any creep that has occurred, even intentional - like moving targets, will result in your described deviation. The app often replaces old cal data on its own. even if you are using a fixed mount in an observatory night to night atmospheric conditions, temp, humidity barometric pressur and layers of seeing effects will throw off guiding cal. It's easy to just hit the trash can icon and let your mount get some noew cal data. LP is also a factor(mine just failed due to moon)
Also, check cable arrangement, any drag or tension will trash guiding pretty quick. Hope this helps and apologies if I miss any followups.