Simulate RGB image with SHO filters

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astrosatch
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Simulate RGB image with SHO filters

Post by astrosatch »

Hi!
Is there any way to make my SHO image to resemble RGB or OSC image? How do I blend channels to approximately get color just like those with broadband cameras? I know there is information missing to get all spectrum, but anyway.

Andrej
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admin
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Re: Simulate RGB image with SHO filters

Post by admin »

Hi Andrej,

The closest would be to;
  • create a synthetic luminance frame from S+H+O (for your detail)
  • create a red channel from (S+H)
  • then load S+H+O as L, (S+H) as R, O as G and B
This should get you the closest to what those bands would look like in the visual spectrum, while making full use of the signal you acquired

All using the Compose module of course. :)
Ivo Jager
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astrosatch
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Re: Simulate RGB image with SHO filters

Post by astrosatch »

Thanks Ivo, that's great. :D I will try it.
Do you have any suggestion what color settings should I use in color module?

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Re: Simulate RGB image with SHO filters

Post by admin »

astrosatch wrote: Tue Jun 08, 2021 4:27 pm Thanks Ivo, that's great. :D I will try it.
Do you have any suggestion what color settings should I use in color module?

Andrej
You'd do something like this;

To create a synthetic luminance frame from S+H+O (for your detail), you would import S, H and O as R, G and B and keep the result (save this away).
Relaunch the Compose module.
To create a red channel from (S+H), load S as red, green, or blue. Do the same for H. Keep the result (save this away)
Relaunch the Compose module.
Load the SHO synthetic luminance (which you created earlier) as L, load the new red channel (S+H) you created earlier as red, load O as green and blue.
"Set Luminance, Color" to "L, RGB".
Now process as normal.

Hope that helps!
Ivo Jager
StarTools creator and astronomy enthusiast
astrosatch
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Re: Simulate RGB image with SHO filters

Post by astrosatch »

Yes, that helps!
Thanks Ivo.

Andrej
Guy
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Re: Simulate RGB image with SHO filters

Post by Guy »

Hi Ivo,

When we create the S+H+O and S+H we should set the 'Luminance, Color' to 'L + Synthetic L from RGB, Mono'
So we save the results as a mono file.
Is that right?

Guy
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Re: Simulate RGB image with SHO filters

Post by admin »

Guy wrote: Fri Jun 11, 2021 7:31 am When we create the S+H+O and S+H we should set the 'Luminance, Color' to 'L + Synthetic L from RGB, Mono'
So we save the results as a mono file.
Is that right?
Thanks Guy,

Indeed, you can do that for good measure (it is the 'proper way' of doing it and and it shows excellent comprehension of what you are doing!). Though when you save as a TIFF immediately, after 'Keep'ing and exiting the Compose module (and indicating all is still linear), then all will be mono anyway.

I should (and want to) really implement some sort of saving and/or buffering functionality inside the Compose module for this sort of thing.
Ivo Jager
StarTools creator and astronomy enthusiast
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