Hi,
When I first got my auto focuser last year, I used the default "Gradient" detection with the "iterative" algorithm (default settings). This worked in some cases and other times it failed (Deadlock or the need of a movement too large). When it worked it worked very fast.

In order to optimize my auto focus I change to SEP detection with Linear algorithm (default settings). This has been working perfectly for months until the other night* (see below). This method is, however, very slow, which results in my target moving pretty far in my FOV when Ekos refocuses eg. once every hour. To eliminate this I've disabled refocusing in the "CCD" (Capture) tab in Ekos. I'd love to have refocusing enabled once each hour or when a temperature change of eg. 2°C occurs.

What to do? Which algorithm and detection method for fast and reliable focusing?


*The other night I experienced my first failure with the SEP / Linear method. I wanted to try out the sequencer in Ekos to create a mosaic of the Andromeda Galaxy. Ekos should do the following in each panel of the mosaic:

Slew, Focus, Plate Solve, Guide and then capture 20 x 180s

The first panel was fine, the second failed due to failure to focus and the third panel was fine. This was my first time with a focus error with the SEP / Linear method. I had to throw my images away though, because M31 wasn't in the field captured at all! No idea why, but that's another problem.

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