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Siril RGB Align Script to remove certain chromatic aberrations.

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Siril Enthusiasts •3 replies•172 views
Brock Johnston avatar
Brock Johnston avatar
I love my Edge HD 9.25 and its 0.7 reducer; however, it has some chromatic aberration around the edge of the frame, primarily shifting the colours radially. I have been manually splitting the image into R, G & B images, re-registering and re-compositing them. This takes a few minutes, so I created a script that runs these steps automatically. Now it takes just two clicks and a few seconds.

This is an image from the lower right corner of a frame, the top panel is raw and the lower has the script applied.

I have attached the script. Feel free to use it, and improve it.

Cheers,

Brock Johnston


RGB Align.ssf
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Dean Ostergaard avatar
Dean Ostergaard avatar
Wait! You're saying I can take my OSC subs, split the channels and process them like monochrome?! 

Why doesn't anyone talk about that?

Maybe they do. I only got into AP this year but this is something I totally missed. I will be studying your script, for sure.

Thanks!

EDIT: I misunderstood what your script does. I thought you were splitting each sub then processing them as if they were different filters from a monochrome session. I wonder if there would be any value in doing it that way. Perhaps split the RGB then use the original for luminance?

This is still a cool idea though and I will try it to see if it can reduce or eliminate the chromatic aberrations I get with my inexpensive Achromat doublet. Thanks again!
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Taman avatar
Taman avatar
Brock Johnston:
I have attached the script. Feel free to use it, and improve it.

Cheers,

Brock Johnston


Thanks for this Brock, it works perfectly! I have the same problem when I use an OSC with my Starizona reducer, the RGB channels are not quite aligned.

The only thing I would do to improve it is to have  the temporary "RGBA" directory created from within the script, otherwise you have to remember to do it first. I can't see an easy way to to this, as Siril does not support a make directory mkdir or equivalent command. For an all in one solution, It could also be added to the OSC_Preprocessing script.

CS, Tony.
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Brock Johnston avatar
Brock Johnston avatar
Brock Johnston:
I have attached the script. Feel free to use it, and improve it.

Cheers,

Brock Johnston


Thanks for this Brock, it works perfectly! I have the same problem when I use an OSC with my Starizona reducer, the RGB channels are not quite aligned.

The only thing I would do to improve it is to have  the temporary "RGBA" directory created from within the script, otherwise you have to remember to do it first. I can't see an easy way to to this, as Siril does not support a make directory mkdir or equivalent command. For an all in one solution, It could also be added to the OSC_Preprocessing script.

CS, Tony.

Taman, I also was hoping I could have the script make a new directory, or delete them files from a previous use of the script, but the commands available did not seem to facilitate it. Thanks for the feedback.

Cheers, Brock