There's no way to input sRGB colors in Blender !! (yes I do know everything on CM)

I met this issue some time ago and already tried to report it but I see nothing changed yet … … …

I know there’s the RGB tab, but it works in linear space so it gives me much brighter colors than expected. Now as an artist I understand colors in the sRGB space that is used by any paint program. So I’d like 0.5,0,0 to be a middle red rather than a bright red.

I see that I can input sRGB values in the HEX field but again, I do not understand hex numbers so I always have to convert for example 255.255.255 to FFFFFF that is a PITA. So how do I input sRGB colors ? Is there a better color wheel than the default one ?

steps to reproduce the issue

  • input 0.5,0,0 in the RGB field
  • flag the material shadeless so you can see the real color on the preview
  • print the screen and check the color value in a paint program, you will see it’s 188,0,0 while I need it to be 128,0,0


Either use a color picker that gives you hex values or try to use HSV values instead. Although HSV has the downside of not being standardized in any way and might give slightly different result.

But I agree that it would be nice to have color pickers in Blender that allow you to punch in numbers in selected colorspace.

Color Management >Display Device: None
http://i.imgur.com/FTAcrt6.jpg

Display device set to none does not give you right colors, instead it messes everything up. When you render with this 0.5 R as in your example, you will not get middle red out of Cycles or BI because when image is saved, it is treated as linear and sRGB transform is applied to it, resulting in not 0.5 but something around 0.7, which is clearly not what you intend to get.

EDIT: it, surprisingly, does work, at least with sRGB based image format like png, just tried it. But it still will mess things up badly in rendering, because objects will be unnaturally bright and this will break secondary illumination. Primary bounces/light will be as expected though, so it could be useful in some cases.

I agree with Kesonmis. Unfortunately disabling the CM (display none) only works with BI. While Cycles needs the CM enabled to render fine.

This sRGB issue also affects imported 3D models from obj dae fbx etc … While textures are converted fine by the CM, diffuse colors are not. Any other software that I use (Lightwave, Poser and DAZ Studio mainly) export sRGB colors in the diffuse channel (that is, when textures are not used). But the Blender importers don’t care about color conversion, and the CM doesn’t care about imported models (apart from textures that are converted fine). So again sRGB colors are badly interpreted as Linear and they appear brighter.

Now Blender Team please it would be about time to do something about this … … …

EDIT: below the same obj model imported into DAZ Studio (or any other software I use) and Blender (sRGB interpreted as Linear and so brighter colors)



Hi, could this be any use of you? (For sure, One need to improve the node-setup, It’s just an idea for solution):
[ATTACH=CONFIG]480559[/ATTACH][ATTACH=CONFIG]480560[/ATTACH]

Here I mixed red and blue; gives purple. I am not sure about the last two nodes, how I should mix it. But it seems it’s working.

That is a conversion from 255.255.255 to 1,1,1 (and you have to divide by 255 though, not 256) but the result is always linear. This has nothing to do with srgb conversions … the formulas to convert from srgb to linear are:

linear = ((srgb + 0.055)/1.055)^2.4

srgb = 1.055 * (linear ^(1/2.4)) - 0.055

http://entropymine.com/imageworsener/srgbformula/

If you can write a script to convert the selected model diffuse colors between Linear and sRGB that would be a proper workaround. The above formulas have to be used for the three R G B components.

EDIT: never mind I found my old original thread where Ricky wrote a cool script to convert things around. It seems it works fine with 2.78c as well … it is just sad that the Blender team did nothing about this yet (the bug report was three years ago) … and the color picker to input sRGB values is yet another story …

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This is the correct answer, thanks for sharing!