Strange V curve


Here are the relevant logs Ken.

Link to Logs

Useful Info

OS: Microsoft Windows 10 Home
.NET: 4.8

Wrt to temperature comp, it seems to be working as designed. That said, you never had a temp comp adjustment made because temperature did not vary sufficiently to introduce an error that would pull you out of the CFZ. If you have evidence to suggest this threshold is wrong for you (changes less than 15 steps are ignored), you can override it.

As for AF, that will take more time to analyze.

Ken I only have a step size of -4 per degree C with the Edge 9.25 and 6D. I checked both equipment profile manager and control panel to see if somehow one of them got changed by accident, but they agree at -4. I never had this problem before with this small of a step size, and have made no adjustments to it lately. I don’t recall seeing it ever go 15 steps (almost 4 degrees C with my setup!) with no temp comp adjustment.

The minimum tolerance for focuser movement due to temp comp is 10% of a single auto focus step. Assuming an auto focus run, at the edges, takes you to ~3x of HFR at focus, then 10% of a single step size is the approximate number of steps that will pull you out of CFZ. Anything less is unnecessary movement and, when backlash compensation is involved, likely to do more damage to focus than good. That said, if you want a lower tolerance, there is a way to set that and I will post here how when I am home.

Okay I understand. Is this minimum movement of 10% of a single step relatively new? Because I am sure I saw it make smaller adjustments than 15 steps in the past. I tend to use image history to watch focus, and do a focus run only if I see it starting to drift. Otherwise I just let temp comp do it’s thing. It can usually drop 5 degrees C and still have my focus perfect just using temp comp, and when I do a focus run, there is very little adjustment to be made. I would be interested in being able to set a lower tolerance just so I can play with it.

Yes, this was requested and implemented in 3.1. You can set the tolerance as low as you want, but need a custom variable to do it.

Okay now it makes sense. I will try it with the 10% tolerance and see how it does. It seems strange to go almost 4 degrees C without an adjustment, but if it isn’t needed I agree there is no point in making one.

Ken do you think my V curve looks like it could be dirt in the gears of the Micro Touch? Or could it be a software issue making it so strange? It is pretty much the same every time - a flat bottom of the V, and a left side of the V that curves outwards. Usually my V curves with this scope are things of beauty and symmetry.
I just got set up again, in California this time, and am trying to decide whether or not to take it apart and clean it. If it has a reasonable chance of it being software related, I may hold off. Thanks.

Distorted V curve the same with the newest update. I still have no idea if this is software related, or if I have dirt in the gears of the Micro Touch. Anyone else out there have an opinion on whether or not this looks like dirt in the gears? I’d rather not open it up in the dusty desert if I don’t have to. But the clock is ticking and I would like to get this fixed before the moon disappears in about a week. My V - curves are usually symmetrical and nothing has changed in my setup.

I see this issue was solved in another thread.

Closing here