Thanks @mikaelA for the fixed viewer. It works great with the log from @esazx. Using it so I can now see the focus results, I agree with your prior comments that the range is not the problem. The positions around 20000 are just fine.
Maple, I think you should be working with step increments of at least 20. The ones less than 10 look to me to be a complete waste of time. You will never get reliable results because they are producing an HFR ratio of high/low of around 1.5 or worse. The ratio should be at least 2.5. These comments of course assume that the reported focuser positions are actually corresponding accurately to real physical positions of the focuser. I have my doubts about that. As @bulrichl mentions, your focus data looks pretty bad. You focuser is either working really poorly, or the seeing/weather was really bad. Since you have confirmed good weather, that leaves the focuser as the culprit.
Have you checked by close visual inspection that your focuser is actually making the requested moves? Your data is very consistent with a serious failure of the focuser to do what you are asking it to do.
Here is what I suggest you do:
- do manual focus to get a really good focus. Turn on image statistics. Capture the visible portion of the image and the image statistics panel, so we can see the star HFR results for the image.
- rack the focuser OUT 50 steps, and repeat the image capture.
- repeat 2) a total of 4 times. At this point you will have 5 images.
- repeat 2 a total of 8 times but move the focuser IN instead of out by 50 steps each time.
Post these 13 jpg images here so we can take a look at them.
Be sure you do the racking OUT and IN using your control software, not manually, after your initial manual focus.
Make your best guess as to which direction you need to apply backlash, and apply a generous amount of it prior to doing your manual fine focus.
Be sure all the images display both the Statistics summary tab and as large an image of your star field as possible with all the selected stars showing their HFR values.
Point your scope approximately toward the zenith for the tests.
Make sure your mount is tracking.
What we should learn from this is whether or not your focuser is producing regular, reproducible changes in focus. We will also get a good idea of what your backlash is, and what direction it needs to be applied. We will also learn what range of step values will work well for you.
You star image in good focus is excellent. You should be getting perfect focus curves on a good weather night, so something is really out of whack.