The new Color module demystified

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Re: The new Color module demystified

Postby admin » Tue Nov 19, 2013 9:10 pm

Puck,

Looking at the two images on my (reasonably well calibrated) screen, as well as my partner's Adobe calibrated screen, the color module and its CIELab conversion algorithms seem to do their job.
The two images are similar in luminosity with the exception that the Color-processed image has desaturated the reds in the darker areas somewhat. To the eye on my calibrated monitor, they appear of equal luminance (just one is colored, and one is not).

Can you make sure your screen is properly calibrated? It sounds like your screen is producing too much red. What sort of screen are you using?
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Re: The new Color module demystified

Postby puckja » Tue Nov 19, 2013 11:45 pm

Ivo:

Thanks for the reply. I am using a desktop monitor (Dell 2209WA). I have also carefully calibrated it using the Win7's calibration function to make sure gamma, brightness/contrast, and color balance. Please let me know if there is other ways to do a better job on that.

I put 4 pictures in one frame and marked the area that I "feel" the nebulosity being reduced:
comp.jpg
Comparison
comp.jpg (218.91 KiB) Viewed 1213 times


The 4th one (2,2) may have been use more "manual develop.

So, on my screen the (1,2) and (2,1) images looks less apparent on the nebulosity. Did your monitor shows the similar amount?
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Re: The new Color module demystified

Postby admin » Wed Nov 20, 2013 12:10 am

Hi Puck,

The "Before using Color", "Starting in Color" and "Adjusted in Color" show (approximately - my screen isn't perfect and JPEG conversion compresses red much more) the same level of nebulosity/luminosity.
"Denoise, then color" shows more nebulosity though.

Is your screen and profile temperature set to 6500K?
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Re: The new Color module demystified

Postby puckja » Wed Nov 20, 2013 7:39 pm

Ivo:

Thanks for checking it out for me. I check my monitor setting and Nvidia setting but did not find the color temperature setting.

I just processed a OSC image shot by another people with DLSR. The color module is doing every wonderful thing. No strange behavior at all. So I suspect that the image from my humble osc cam may have some "false" information (such as the color artifact around bright star, which seems to due to aliasing effect?) that confused the color module. The solution may be just need to go longer exposure time to improve the SNR.
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