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Canon 6D Stock Red Response

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#1 unitron_man

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Posted 28 June 2022 - 08:36 AM

Hi

 

I just picked up a non-modified Canon 6D. 

 

Below is a 1h 36m shot of the milky way, ISO 1600 with 120sec subs.

 

I'm using Siril to process the image.

 

The question....

 

Why are the H-alpha regions,  Lagoon, Trifid and Omega nebulae showing up basically white? Why aren't these more red?

 

I believe I have the color balance correct.

 

I understand that an astro-modified camera will improve the red response.

 

I've used the Arcsin stretch in Siril to preserve the colors while stretching so that isn't it.

 

It is with a Canon 70-200mm at 200mm and f/2.8 with a B&W F-Pro protective filter.

 

The thoughput at H-Alpha on this filter is at least 95%

 

Any ideas?

 

Thanks

 

Attached Thumbnails

  • Lagoon_Trifid-Rev2-8bit-cn.jpg


#2 vidrazor

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Posted 28 June 2022 - 11:52 AM

Did u use photometric color calibration?

#3 unitron_man

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Posted 28 June 2022 - 12:53 PM

Yes, I selected a region around M8 and did photometric calibration.



#4 vidrazor

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Posted 28 June 2022 - 02:07 PM

Try a manual correction and see what you get. Sometimes photometric gives odd corrections. I doubt your camera is the problem.

Edited by vidrazor, 28 June 2022 - 02:08 PM.


#5 sharkmelley

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Posted 28 June 2022 - 04:46 PM

Do those areas look white in a single sub opened in Photoshop or RawTherapee with a daylight white balance?




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