After some work, I got my Esatto focuser to work on the C11 Edge, with the auto guider, filter wheel and ASI1600MM - all within the required 146mm back focus.

But now I am struggling to get EKOS to autofocus. I am imaging through a C11 Edge at 2800mm focal length f/10. The HFR bounces around too much to allow EKOS to find a good focus. I tried 1 second exposures, 2 second, 5 and even 10. I tried averaging the HFR values 2 and 3 times. Regardless, I would see HFR values like 310, 345, 320, 300, 360 etc…. This made determining the exact best focus impossible.

I never had this issue with my small 349mm f.4.9 WOStar71. The HFR values were consistent between exposures. AutoFocus was a breeze and reliable.
I don't know what the best settings to help stabilize HFR values at this high focal length. I tried many different combinations, from using gradient, centroid, and SEP to changing the tolerance settings. Nothing seemed to fix the issue that my star HFR values jump around too much between equal exposures.

Any ideas I can try?

Peter

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