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Gräck
11-14-2008, 10:58 AM
Hi,

I have a dark blue and a bright yellow light in my scene. Now I want to desaturate these lights correctly. So I have put the light colors into Photoshop and desatured them. The resulting values are used as the new color values for the Max lights. I have rendered the image with these desaturated lights again and compared the render with the previously, saturated render. The brightness doesn't match. The dark blue light is actually darker than the desaturated version. And the bright yellow light is brighter. But I want to have the exact same intensity as before.

The problem seems to come up in Photoshop. When using the desaturate function, it looks like the grey color doesn't match the intensity of the saturated version of the color. Darker looking colors (more saturation) become brighter when desaturating them, whereas brighter looking colors (less saturation) become darker when desaturating them.

Can you follow me? What can I do to maintain the intensity perfectly when desaturating all lights in the scene? Do I have to manually adjust the lights or is there an automatic way? Where are the lighting experts?
JamesMK
11-14-2008, 11:27 AM
This is a long-shot, but it might be that you'd get correct results in Photoshop if you work in LAB mode rather than RGB, since that way luminosity is handled as a separate thing entirely detached from colour. Might be worth a try at least.
Gräck
11-14-2008, 12:16 PM
Interesting... this seems to work much better. The resulting brightness in the renderings (B percentage in Photoshop) still doesn't match (now the dark blue light is darker instead of brighter), but it looks much better.

However, optically, now the resulting intensity looks a bit too bright for the bright yellow light and a bit too dark for the dark blue light. So somewhere between desaturing in RGB and desaturting in LAB should be perfect.

Thank you so far, James!
gerardo
11-28-2008, 06:23 AM
Do desaturate colors in the same working color space. Either for matching the rendered image or for matching the desaturated lights colors.



Gerardo
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11-28-2008, 06:23 AM
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