Hi Morelli,
Thanks for posting the screenshots. I'll concentrate on the Linear 1 Pass focus runs. From your signature it looks like you're using a MAK180 SW and ASI183MM PRO. I don't know if you have a reducer, if not you're at FL 2700 f/15. The pixel size is 2.4 microns which gives an image scale of 0.18"/pixel for bin 1. I see you're 2x2 binning which would be 0.36"/pixel.
Are you running Autofocus with the Bahtinov mask on? Or adding it after Autofocus completes in order to compare the focus position with the Bahtinov? I'll assume the latter. Out of interest what is the focus position that the Bahtinov gives you?
You imply you are using a single star to focus rather than using multiple stars. Is that correct? Either should be OK but I always use multiple stars (but am at a much shorter FL). If you do use multiple stars then its worth checking the "Use weights" option.
The curves in general look ok in terms of number of points and total HFR change from min to max. I suspect, however, that with the Mak you will be suffering from donuts when you move out of focus. I can't tell from the screenshots though.
Given your FL, the exposure times seem short (1 and 3 seconds). You are averaging over 3 or 5 frames. Personally I would increase the exposure time maybe to 4 to 5 secs and average over 1 frame. If you have a lot of saturated stars at 5 secs you'll have to reduce the exposure time.
When you are on the first and last datapoint (out of focus) how is the star detection? You can move to that focuser position and take a frame. If you zoom in you can see how well (or not) star detection is working. I see you are using the "SmallStars" SEP profile. Is there a reason for that? Have you tried the "Focus" SEP profile?
One other thing we could try is if you set the "Save Focus Images" option. The focus images are saved in the same directory as log files. You could turn this option on, do a focus run, then send me the images. You probably will want to then turn the option off so you don't fill up your disk. I'm happy to play around with star detection with these. This is how to turn the option on..
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One more thing... backlash. The v-curves don't show any evidence of backlash which is a good thing. But how are you controlling it? What settings do you have? When Linear 1 Pass goes to the solution the algorithm has calculated, its imperative that the focuser is able to perform that final outward motion with well controlled backlash. So there are a couple of ways to do that:
1. Does the MyFocuserPro do its own backlash control? Is this what you are using? If so, does it manage mirror flop (if you have any on the Mak)?
2. If the MyFocuserPro is not controlling backlash how are you controlling it in Ekos? Is the driver controlling backlash? If so, are you sure this is working correctly?
3. AF Overscan should work with the Mak to overcome any flop. Are you using it?
Sorry for all the questions, but hopefully through the dialog we'll get a good solution.