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.

New KStars/Ekos Module: Analyze

1 month 4 days ago
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Posts: 149
New KStars/Ekos Module: Analyze #60580

hy wrote: Obviously, it looks suspicious that all the HFR values are 0.940.
It would be good to know if the system is computing them wrong, or if they are being recorded wrong.
Did you say that they were being displayed correctly on the fitsviewer?
It will be hard for me to debug -- so the more info you can provide (and of course the more debugging you can do, if you're comfortable with that)
the better.

BTW, what kind of camera, etc?

The fits viewer does give numbers that are a bit different and seem more correct. I'm happy to debug.

The camera in this case is an FLI ML16000.

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1 month 1 day ago
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New KStars/Ekos Module: Analyze #60736
Replying to @dokeeffe from his comments on indilib.org/forum/general/7863-the-new-analyze-tab-thanks.html


Thanks again for trying out Analyze. I agree that an SQR-type measure is something that should be in Analyze.

SQM itself is possible, but there are complications . For example, I believe the right way to do it is to subtract a dark from the signal,
get the median pixel value, multiply by the inverse of the bandwidth of the optical system, (e.g. if you're using a Blue fliter, or more extreme Ha,
fewer photons reach the sensor than if you're using an L, or a 1-shot camera) then do a little math--have it written down somewhere ;)
This is complicated by the need of the dark and the need to know the filter bandwidth, but certainly possible.

I did provide "Sky Background", the checkbox furthest to the right on the 2nd line, which is the background sky value SEP (Sextractor)
computes when extracting stars, but I see yours isn't populated. I think you need to be using SEP MultiStar guiding to get that value.
I can improve requirements like this after 3.5 when SEP improvements being done by @rlancaste are scheduled for release
You might SEP MultiStar guiding and look at the sky background feature if possible.

Another straight-forward thing I could do is simple add the median pixel value, which is "pretty much the same" as the SQM, except of course
it's linear, not log, has an offset, is affected by filter bandwidth, ... ;) I have gone through the exercise of computing SQM from median pixel values.
Obviously SQM would be more ideal, though.

Adding new features (now that I've filled up the 2 rows) would required a little UI redesign, but I don't think it's too bad. I had planned on organizing
these features into "guiding", "image" and "mount" sections, and SQM and ellipticity would fit in the image section nicely.

What do you think? Would the basic median work for you? Does sky-background look OK as is?


PS I see you're afflicted with the same "after focus guiding correction" that afflicts me.
I'll definitely look into this further someday, if someone doesn't beat me to it.
The following user(s) said Thank You dokeeffe

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1 month 1 day ago
Gold Boarder
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Posts: 392
New KStars/Ekos Module: Analyze #60739
Thanks Hy,

I was thinking of SQM from a unihedron sky quality meter. If there is one is connected to INDI then collect data from it. I think its probably very difficult to estimate real SQM (in units of MPSAS) from an image.
So basically if there is an SQM device and it is connected with INDI, collect that data every x min or at every capture.

Yes, I have that after focus correction :-) As a work around I include a 10second wait in all my Ekos sequences. That 10 seconds is usually enough for the guiding to get back on track. I was thinking to try and not suspend guiding during focus next time and see how it goes.

Thanks again for this amazing feature!

Celestron C11 iOptron CEM120 Atik 383L
HP8300 Elite i5 running Xubuntu, Indi, Kstars & Ekos
Roll off roof observatory
Battling Irish weather

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3 weeks 25 minutes ago 3 weeks 25 minutes ago by schwim.
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Posts: 149
New KStars/Ekos Module: Analyze #61223

Back to the HFR values as represented in the Analyze tab (and sometimes not). I believe this is related to whether the "Use FITS Viewer" setting is active. I tend to keep it off as I don't want the popup - seeing the result on the Setup/Status tab is sufficient for me in most cases. So, when that option is off, the HFR values are 0.00, if anything at all. If the option is on, we get values.

Any chance the HFR numbers can be gleaned from whatever mechanism decides if focusing needs to happen before starting the next exposure?


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