John replied to the topic 'Auto Focus failures' in the forum. 3 months ago

Hi David,

I had a quick look at the log...
Starting focus with Detection: "SEP" Algorithm: "Linear 1 Pass" Box size: 64 Subframe: no Autostar: yes Full frame: yes [ 5 %, 60 %] Step Size: 50 Threshold: 150 Gaussian Sigma: 1.5 Gaussian Kernel size: 5 Multi row average: 3 Tolerance: 1 Frames: 1 Maximum Travel: 200 Curve Fit: "Parabola" Use Weights: no R2 Limit: 0

A couple of things jump out at me.
1. Max Travel set to 200. Why is this so low? You are constraining the autofocus run. I would set it to 2000 (unless that gives you other issues). If the run is constrained then you won't get a proper curve. I also see log failures due to this.
2. Use weights = no. I would recommend setting this to yes.

If you send me a couple of focus frames (1 in focus, 1 as far out of focus as the autorun takes things) then I'll take a look at these. Be good if you can screenshot the SEP profile options you are using as well.