Gamma 2.2 and diffuse color

[Komposer]

Hi,

I need some hints.

When I set my diffuse color to a nice dark nearly pure red tone..
then the material sample shows a realy other tone..
the color becomes more orange than red.

Its a general prob, when I use gamma 2.2 setup.
the colors whashes out.
but only diffuse materials, not the textures loaded with gamma 2.2 input correction.

What is wrong?


Thanks for help

[Zdravko]

Would it be possible to attache a simple scene with that issue. We can't reproduce the issue with the Material sampler here.
There is an option "Linear workflow" in Color mapping roll out, which forces V-Ray to automatically apply the inverse gamma correction for all colors and textures in the scene.

Also, more information about LWF can be found here:
http://www.chaosgroup.com/forums/vbu...t=exr+brighter

[cdavis]

I thought the "linear Workflow" button was only meant for old scenes that hadn't been set up with a gamma 2.2 workflow to begin with?

Do you have affect swatches on in the colour mapping section? as it looks like it might!

[Zdravko]

Yes, you can use the "linear Workflow" option with old scenes as well. But still a lot of users use it for their LWF for new projects.
I'm sorry for the misunderstanding, the Affect swatches option was the reason for the color difference in the material sampler.

[cdavis]

ok.... so in the manual it states

"Linear workflow - when this option is checked V-Ray will automatically apply the inverse of the Gamma correction that you have set in the Gamma field to all VRayMtl materials in your scene. Note that this option is intended to be used only for quickly converting old scenes which are not set up with proper linear workflow in mind. This option is not a replacement for proper linear workflow."

so what is a proper linear workflow??

if I am setting up a new scene now what should my colour mapping settings in the render global look like? and do or do I not add the "bitmap gamma input " node to my textures ?
I'm hoping for a direct answer please , not a link to a million other posts & discussions on linear workflow.

Thanks

[Zdravko]

Unfortunately we can't provide you with one universal linear workflow which you can use.
There are many approaches to do this and it is up to the artist to choose one.
I sent you the link to the 3 most common workflows which we advise our customers to use:
http://www.chaosgroup.com/forums/vbu...t=exr+brighter
this is the best guide that we can provide you with and from then on it is up to you to decide which method you want to use.

[cdavis]

OK, thanks.

in Maya what is the equivalent of the "Affect Material Editor" used in the max set up mentioned in the link ?

Thanks

[vlado]

In the Color mapping section of V-Ray, there is a "Affect material swatches" option.

Best regards,
Vlado

[bazuka]

ill do some test and see if i got everything right too

[snivlem]

edit: nevermind.

[cdavis]

ok, cool. thanks for the tips Zdravko. Now i know I'm not looking for a singular perfect set up it makes it a lot easier. I think I now have a linear workflow which I'm happy with.
thanks
CHris

[cdavis]

is there any way in Maya to pick colours in the colour picker as sRGB values, but it converts them to linear . currently i'm picking a colour by eye, which is basically picking a visual srgb colour in a linear colour picker. so if I were to render that , its washed out. So I am taking my visually picked colour values 0-1.0 & squaring them which works, but I was wondering if there's a quicker way to do it. Also it seems values are very low once converted, like a dark grey plastic will have a value of 0.004.

hope that makes sense!

[treyharrell]

The quickest way to do this is to attach a gamma node, set all 3 fields to .454, then use the swatch picker on the gamma node's value.

--T