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Bizarre behaviour of Ekos-made frame after debayering

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Hi there,
Looking for a clue for the issue following.
One day I took a series of 20 sec frames (gain = 200) with ASI178MC and the next day made 60 sec frames at gain = 100. After debayering at PixInsight one series looks green and another blue.
Could you explain how this is possible. Settings were the same (with exception of gain&exposure), FITS Headers were the same as well.

I suspect that Ekos+INDI under Ubuntu could be blame for this because I’ve never seen such phenomenon under APT@Windows.
1 year 8 months ago #84244
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Could this be some autostretch artifact? The data from the camera are stored AS IS without any pre-processing or data shifting taking place.
1 year 8 months ago #84276

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Thank you for your reply, but I think it isn't connected with autostretching, debayering and something like that. When I open both files in PixInsight and zoom it up the differerent patterns appear.



Left one is 'green' image after debayering (and its pattern looks 'correct') and right one is 'blue'.
'Green' image is one of 25 green images taken and 'blue' is one of 25 blue images taken next night, therefore some systematic behavior is occured and I try to find a sensible reason for it.
1 year 8 months ago #84325
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"Left one is 'green' image after debayering (and its pattern looks 'correct') and right one is 'blue'."
Wondering if a wrong debayering pattern is being applied hence a pattern is being left behind. Does the fits header of the raw image give you a clue on the pattern that the driver has picked up?
Last edit: 1 year 8 months ago by AstroMuni.
1 year 8 months ago #84358

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Fits headers are the same (with exception of time, coordinates, exposure and gain). Pattern tags are BAYERPAT= 'RGGB ' for both series.
It's interesting that both images in ASIFitsView looks similar. But ASIFitsView makes not only debayering but color calibration as well.
1 year 8 months ago #84361

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If you can post both raw images here others maybe able to help.
1 year 8 months ago #84366

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No problem, I would be grateful for any help.
disk.yandex.ru/d/WoZ5h9l9gSToxg
1 year 8 months ago #84373

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I opened your images in Siril and it indeed looks like the bayer pattern on the 60s image is different, but I am no expert and havent compared bayer patterns on my different images. Perhaps time to do that :-)
My understanding is that the bayer pattern is hardware based so not sure how it changes??
Here is a suggestion incase its an ASI INDI driver issue. Give it a try using the ASI provided tools and see if it generates differently.
Last edit: 1 year 8 months ago by AstroMuni.
1 year 8 months ago #84386

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Thanks for trying to help!
Unfortunately, I can't make an unambiguous conclusion about the reason for this strange behavior, since over the past year I have changed both the operating system and shooting software. Even ASI178 isn't quite familiar to me (my main camera is ASI071MC). But by some indirect signs, I can conclude that the reason could be connected with ASI INDI driver (Some of my friends have also experienced similar behavior).
Anyway, next time I'll try to make frames with Ekos and with ASIImg as you suggested.
1 year 8 months ago #84396

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