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INDI Library v1.8.5 Released (19 Apr 2020)

April 2020 release of INDI Library v1.8.5 introduces new drivers while providing fixes and improvements to existing devices and core framework.

For those with focus issues

2 months 1 week ago
hy
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For those with focus issues #51221
Yes, that's it, not absolutely necessary to avoid the center/typical target area, but if you can get plenty of stars elsewhere then why not. If you're starved for stars then see if it works fine including it. I guess removing the edges would be avoiding areas that can have more coma, which might adding noise to the hfr values.

I just images m95/m96 where the galaxies weren't centered but I didn't change the annulus, and had no issues, so it's just something to make things run more automatically, that I've adopted from others, and I've seen bad star detections, eg in the center of m31, but the averaging and outlier removal would likely have avoided issues.

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2 months 1 week ago
DerPit
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For those with focus issues #51223
Two things coming to my mind reading this:
  1. Star detection
  2. As Hy says, use SEP. It's what sextractor uses. And I wonder if results would get better if you switch the camera to 8bit. PHD2 seems to perform (for me) substantially better in 8bit mode.
  3. star field area
  4. One other reason to use a ring is a (possible) field curvature. For 1-star focus a suggestion also is to use a star half or 2/3rd away from center, then both center and rim would still be in the depth-of-focus range...

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

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2 months 1 week ago
mlarsson
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For those with focus issues #51241
Hi!

So I am testing full field with SEP as star detection. One thing that happens here, is that the focuser moves a lot! The first move is 500 tics. BUT: I have set initial step size to 100 and Max Travel to 400... So how come it moves this much? I have those more conservative values so as not to land it too unfocused settings, increasing the risk for misidentification of stars.

Did I miss something?

Magnus


C8, Losmandy G11, Canon 1000D astromodified.

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2 months 1 week ago 2 months 1 week ago by mlarsson.
mlarsson
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For those with focus issues #51243
Sorry, that was not caused by full field. But by "Linear". I had it set to Linear algoritm. When I switch to Polynomial, it behaves more reasonably.

Log attached, regarding the linear stuff. By the end of the log - I guess it is a bit long-ish, but by the end there are focusing with Linear.

Magnus


C8, Losmandy G11, Canon 1000D astromodified.
Attachments:

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2 months 1 week ago
hy
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For those with focus issues #51253
Magnus,

Sorry, looked at your log and something is clearly broken (I mean likely software) for your setup.
I'll look further. Which moonlight focuser are you using?

It didn't look to me like you had any successful focus runs with Linear. Is that correct?

Hy

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2 months 1 week ago
mlarsson
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For those with focus issues #51254
Hi!

No problem, just glad if I can on the one hand, understand something, on the other, contribute to your great work!!! :) Maybe I missed some settings?

I'm doing polynomial now, works great with full field :)

I have a MyFocuser Pro (1st version), that I built myself with an arduino board. It controls a Baader Diamond focuser on my Skywatcher 100 ED Pro, f 7.6.

Magnus


C8, Losmandy G11, Canon 1000D astromodified.

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2 months 1 week ago
hy
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For those with focus issues #51255
Magnus,

I may not have much time later today to look into it, but a quick initial look shows that:

Now I'm not sure if it's sortware or hardware.

it is asking the focuser to move to a certain position to start, and the focuser doesn't get there, and the Linear algorithm doesn't
reset to the new position that the focuser is insisting on.

For instance, in the first attempt.
Starts at 10760
Linear wants to start its sweep at 11160, but does this by planning to go out to 11660, then back in 500 to 11160 (It doesn't violate max position, but it is ignoring max travel)
So it requests that the moonlight go to 11660. Indi copies that. But the focuser reports getting to 10916.
*** Do you have some kind of backlash removal active or something like that that could be confusing it?
The Linear focus seems to ignore this discrepancy and then moves back in by 500 which gets it to 10416 (instead of 11660) and now things are messed up and Linear isn't recovering well.

2nd focus session:

Starts at 11000
Plans to go out to 11900 and back to 11400.
But only gets to 11134 and then goes back to 10634.
Same finish as above.

I'm not sure why your focuser is not going out to the position requested in the first outward movement.
It seems to work fine for the inward movements, but not the outward movements.

Does it all work well in polynomial?

Can you manually command it to move out to these positions and back in?

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2 months 1 week ago
mlarsson
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For those with focus issues #51256
Hi!

No backlash removal that I know of... to the best of my knowledge, there is none in the MyFocuser Pro ver 1. And no mechanical stuff like that.

I can try tomorrow to see if I manually can move it to those positons. Right now it is imaging...

Polynomial works fine, and tonight even better than usual (if because we have real clear skies, or because I use full field with annulus set properly, I do not know.

I'll try tomorrow.

Magnus


C8, Losmandy G11, Canon 1000D astromodified.

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2 months 1 week ago
mlarsson
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For those with focus issues #51267
Hi!

So, I have no problems in moving to those positions and positions beyond them (in the 12000 range) manually.

Magnus


C8, Losmandy G11, Canon 1000D astromodified.

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2 months 1 week ago
ChrisRowland
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For those with focus issues #51273
Some focus problems are caused by outliers - hot pixels and extended sources such as galaxies. Would these be more effectively removed by changing the full field HFR determination to use the median rather than the average HFR value. This will cause extreme values to be ignored quite naturally.

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2 months 1 week ago
gilesco
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For those with focus issues #51275

ChrisRowland wrote: Some focus problems are caused by outliers - hot pixels and extended sources such as galaxies. Would these be more effectively removed by changing the full field HFR determination to use the median rather than the average HFR value. This will cause extreme values to be ignored quite naturally.


Or even better discard the 5% smallest and biggest outliers and take the mean of the remaining detections.

__
I blog my progress: www.coochey.net

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2 months 1 week ago
DerPit
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For those with focus issues #51277
With 50+ stars you might as well do a winzorized sigma clipping. Or maybe even linear clipping. For only one 'pixel' the computational overhead is not noticeable.

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

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