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INDI Library v1.8.6 Released (21 Aug 2020)

August 2020 release of INDI Library v1.8.6 introduces new drivers while providing fixes and improvements to existing devices and core framework.

For those with focus issues

9 months 2 days ago
Frank L
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For those with focus issues #47250
Hi Hy,
as Chris said, my Celestron can have BL but especially the problem of the flip mirror when you change direction for focusing. This is the reason why I can not do autofocus, but maybe I do it wrong especially over the duration of the subs?

Merry Christmas to all !

Frank

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9 months 2 days ago
DerPit
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For those with focus issues #47251
Hy, thanks for this change, and Jasem already approved your submit :)
I'm having clouds (of course - it's New Moon.... :( ), but tomorrow night is predicted clear. I'll try the changed routine then and report back.

Chris: Yes, I agree BL compensation should eventually work independent of the focus algorithm (and, as I mentioned, probably also independent of the driver). One reason for that IMO is that the concept of 'outward' and 'inward' is really only known to EKOS (or am I completely wrong there?). But for now, the linear algorithm is a perfect test bed to check the best implementation. And getting it in the device independent part has several traps (like what to do with a driver-internal BL compensation? Should it be switched off when end-inwards is active?). So it's good to have one algorithm that uses it already now...

openSUSE Tumbleweed KStars git INDI git
GPDX+EQMOD, CEM60EC, ASI1600+EFW+EAF+ASI290 mini

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9 months 18 hours ago
DerPit
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For those with focus issues #47276
Hi Hy!

Just playing with the new version. The plateaus are now gone, that's very nice. Attached are three runs, the first with a step of 30, the second and third with 20.
The derived focus positions were 45638 (step30), 45648 (step20 1) and 45608 (step20 2). That the last one is lower for sure is a (real) temperature effect, it's currently dropping at 2 degrees/hour. So that's nothing to worry about.

But the stop criterion is still a bit sharp - it will largely be affected by seeing. Especially the second and third run got a good frame and stopped, both times I'd say a bit too early. Not sure though how to catch that other than doing a polynomial fit including all points after also the fine scan went (clearly) through the minimum. The latter might suggest to wait even one exposure longer for both repeats to make sure it wasn't seeing bending it up (I think this happened in the second scan). And in that scenario it would also need a final move-out and then back in to the detected focus.

But the general shape of the curves looks promising to me :D

Cheers,

Pit


openSUSE Tumbleweed KStars git INDI git
GPDX+EQMOD, CEM60EC, ASI1600+EFW+EAF+ASI290 mini
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8 months 4 weeks ago 8 months 4 weeks ago by El Corazon.
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For those with focus issues #47328

ChrisRowland wrote: This is a common way of implementing backlash. All moves approach the final position from the same direction and distance. This eliminates backlash by ensuring that all moves finish in the same direction. Backlash is your M parameter.

The example shown seems to have found the minimum with the focuser moving out instead of in but there is nothing except friction stopping the camera moving out the 100 steps of the backlash and being out of focus by 100 steps. If the focuser finishes by pushing the camera in which, with the telescope looking at the sky, will be up there will be less chance of unepected focus shifts.

Chris



I am using a self-built, timed DC motor driven autofocuser. This is my decidedly low-tech solution how I overcame the friction/focus shift/slippage problem.

A couple of rubber bands:


Atlas Pro AZ-EQ, ASI1600MM-Pro, ASI120MM-S, ES102ED, WO-Z61, Nikon D3300, ASI-EFW, ZWO LRGB,Ha,O3,S2 filter set
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8 months 1 week ago
universalmaster
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For those with focus issues #48194
Hi!

I now tried this, and I seem to just get an long loops of moving in's and moving out's with the same step until it finally reports an error. I also have to set the Initial step size quite low to not get errors like this
[2020-01-19T19:09:49.966 CET DEBG ][ org.kde.kstars.indi] - FCUSB1 Focuser : "Error: Invalid range for FOCUS_TIMER_VALUE. Valid range is from 0 to 5000. Requested value is 20000 "
[2020-01-19T19:09:52.093 CET DEBG ][ org.kde.kstars.indi] - FCUSB1 Focuser : "Error: Invalid range for FOCUS_TIMER_VALUE. Valid range is from 0 to 5000. Requested value is 10000 "
[2020-01-19T19:09:58.382 CET WARN ][ org.kde.kstars.ekos.focus] - Focus GSL error: invalid argument supplied by user

The last line persists even with a small initial step size.

I use a FCUSB focuser.

Best Regards,
Søren

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8 months 1 week ago
El Corazon
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For those with focus issues #48196
I also use FCUSB, did so just last night with the latest stable version and did not have that problem. What is your initial step size, what's the maximal step size, what is the maximal travel and what is the tolerance setting? Which algorithm did you choose? Linear v3, polynomial, iterative?
What focuser are you using? Can you provide logs?

Atlas Pro AZ-EQ, ASI1600MM-Pro, ASI120MM-S, ES102ED, WO-Z61, Nikon D3300, ASI-EFW, ZWO LRGB,Ha,O3,S2 filter set

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8 months 1 week ago
universalmaster
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For those with focus issues #48197
Polynomial and iterative seemed to work fine, the failure was for the linear. There is somewhere a limit of 5000 on the maximum step, which I go above if I set initial step to what I use in polynomial and iterative (2000). If I set initial step lower the algorithm does something, but it does not reach focus.

I don't have more from the logs than the above, sorry.

This was with the nightly build, as the latest stable give me a focus error when moving inwards, which seems to have been fixed, but the nightly does not.

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8 months 1 week ago
wvreeven
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For those with focus issues #48202
The linear algorithm in the nightly builds currently is under development. If you send me a PM with your email address then I’ll be happy to add you to the email conversation between Jo, Hy and me about this.

ASI6200 and filter wheel with a SkyWatcher Esprit 80 ED on a SkyWatcher HEQ5-Pro
ASI1600MM-Pro Cooled and filter wheel with an 8" TS Ritchey-Chrétien on a SkyWatcher EQ6-R

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8 months 1 week ago
universalmaster
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For those with focus issues #48203
Ok, thanks for letting me know. I will stick to the stable from now on. I hope the focus error fix will appear soon in the stable release, this was the only reason to use the nightly.

I think I need to get a lot more under control with my equipment before I can contribute anything, but thanks for the opportunity!

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8 months 1 week ago
wvreeven
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For those with focus issues #48214
No need to revert to stable as long as you are aware of the potential issues with the linear algorithm. You said that polynomial and iterative work so that’s great.

ASI6200 and filter wheel with a SkyWatcher Esprit 80 ED on a SkyWatcher HEQ5-Pro
ASI1600MM-Pro Cooled and filter wheel with an 8" TS Ritchey-Chrétien on a SkyWatcher EQ6-R

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8 months 6 days ago
hy
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For those with focus issues #48263
As Wouter said, he, Jo and I are iterating on improving this algorithm, but would be happy to get additional testers.
I think things are better with the latest nightlies (the most recent one will show "v3" on the menu where you select the algorithm: "Linear (Experimental v3)"

One of the weaknesses is that you need to select an appropriate step size--ultimately we should have a "wizard" for that, but until things are more mature, I think it should be done by hand.

Søren: As I am not familiar with your particular configuration I can't recommend anything, but probably each step size might be the kind of small steps you'd use manually when you were somewhat close to focus. If you go too small, though, the algorithm can get caught in the noise of the focus system.

Søren: I suspect you weren't using the latest release, because there was a bug in there a week or so ago that caused that last output line. Are you sure you're using v3?

Pit: join in!

Anyway whoever does want to provide feedback, please have logging to a file turned on with at least verbose, file and focus logging enabled.

Note, you don't have to waste a nice evening to do these tests. If there are clouds, so it's not the ideal evening to image, but there's a patch of clear sky, you can try a few autofocus rounds pointing at that patch.

Thanks,
Hy

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8 months 5 days ago
DerPit
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For those with focus issues #48367

hy wrote: Pit: join in!


Hy, I'd love to, but as I wrote in my last mail (did you actually get it?) I'm in Sweden at the moment, without a telescope :sick:
So I'm only following the discussion, but cannot do much testing...

openSUSE Tumbleweed KStars git INDI git
GPDX+EQMOD, CEM60EC, ASI1600+EFW+EAF+ASI290 mini

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