John,

The Unknown Error is now gone. I'm running v319 of Robert's firmware which is the latest.

Sorry, yes I mean Quadratic! I switched to Parabola and it seems to work fine every time. I did try Hyperbolic for a couple of cycles and it also seems to be working well for me. When on Quadratic sometimes it chooses the final sample position as the solution even though the value calculated on the chart is very different. As you see in the screen shot above. I really don't think this would be anything to do with backlash settings.

The next time I power it up I can send a screenshot but I can confirm that both in and out are disabled and all values are zero. The image in the manual is using the Windows test application. These can also be set in the INDI driver which is also set to disabled.

Thanks
Ken

Hi Ken,

Well that sounds like an improvement after the firmware upgrade if Hyperbola and Parabola are working as you were having problems with Hyperbola / Quadratic before. It would be worth sending another log when you next have a problem (or if you have one from the last session where you had the issue from Quadratic).

Just for info, Quadratic fits a parabolic curve using an older curve fitting routine that's been around in Ekos for a few years. Parabolic does the same thing mathematically as Quadratic but using a new solver that was introduced with Linear 1 Pass. So there is no real reason to use Quadratic and I would encourage people to use Parabola or Hyperbola. However, you shouldn't be getting the error you are getting with Quadratic so I'm happy to look into it and hopefully help you resolve it.

Rgds,
John.

Really exciting feature, Looking forward to seeing AF Backlash Comp return in 3.6.2 ! Measuring the backlash is a novice's nightmare.

Best Regards，
Lanco

I have Ekos running a myfocuser2 with the latest .321 firmware on Ubuntu 22.04 and, despite all my efforts, I have the problem with linear 1 pass algorithm moving to the wrong solution.
For the moment I'm stuck using polynomial algorithm, which by the way works ok since my focuser apparently has little backlash. But the V-curves I get with linear1 are superb... so, since for what I understand there are no other options, I'm really looking forward to 3.6.2 hoping it will solve the problem.

Hi Massimo,

Its difficult to comment on your issue without a log of the problem. If you could post a log with the following settings I can take a look...

Thanks a lot John. I'll take a log as soon (two weeks apparently) as the "monsoon" pass by.

However, my guess is that I'm facing the same problem faced by others of a fight between the backlash compensation of the driver and Ekos. I tried all the possible settings in the Indi driver but I got only "scattered results": some times the algorithm moves to the solution, some times it sticks to the last measurement (as in the attached pictures). I'll keep trying and record a log.

For what I understand in the nightly and in 3.6.2 it is possible to overcome this by muting the backlash compensation in Ekos... right?

I have the same focuser and firmware. Unfortunately, the same problem as well. I don't think it's the focuser firmware because it did it with the older firmware as well. I'm awaiting the new release but for now I use 1-pass parabola and it seems to work OK for me.

Ken

Hi Massimo,

Yes, there is a new option in 3.6.2 (currently in the nightly releases if you can take them) to disable the backlash compensation in the Linear 1 Pass algorithm. For now if you set backlash=1 you will minimise (but not completely disable) backlash. My "guess" is that the Linear 1 Pass backlash compensation is somehow conflicting with the myFocuserPro2's own backlash processing so by disabling it in Linear 1 Pass it may improve things.

Of course, this is just a theory so may prove not to be correct, in which case we'll have to look further into things.

Hi John, I red about the "set backlash=1" thing in previous posts... what I still do not understand is why in the focus module of my Ekos installation the backlash compensation is greyed out. It looks like the driver is not recognizing the myfocuser2 as backlash capable... the more I dwell into Ekos the more mysteries I found, I think it's part of the game!

Question: is there a way to test that the software side of the focusing operation is working without waiting for a starry night? In the end, at least on a first basis, I have just to check that the last move issued to the focuser is the same number as that calculated from the curve fitting process.

Ah yes, i just checked the driver code (myfocuserpro2.cpp) and is doesn't support Backlash. So in this case Ekos will grey out the backlash field. So you can't set it to zero.

Generally I use the focus simulator but here the issue is with a specific focuser so you'll have to connect that. The issue (from Ken's log for example) is that Ekos issues a command to move to position X but, for some reason, the focuser moves to Y and reports "done". Seems like this happens on a direction change from inward to outward (hence my suspicion that this is backlash related).

You could try imitating the focuser motion by connecting the focuser. You can enter a position to move to, then hit the goto button. So start at say 1000 (or whatever makes sense for your equipment). Move in to 800. Then 600, then 400, then 200. Then simulate the move to the final position by Move 1100, followed by Move 1000. Somewhere in the last couple of moves things go wrong in the autofocus routine - be interesting if you could replicate it with individual moves.