Colour Management and Vray

[Dave_Wortley]

Vlado, I'm doing a bit of research into colour management on wide-gamut displays and trying to get consistant results between our PC and Mac departments.

Are there any plans to impleament a fully colour managed VFB for vray?

It gets a lot more complicated than just Gamma workflows, and here is a very good article for anyone that is interested. Actually very important for everyone to understand.

http://www.artstorm.net/journal/2009...mut-dell-2408/

It would be excellent to be able to load a monitor iCC profile into the VFB and be sure we're looking at the same thing as there will be in photoshop.


Rgds


Dave

[vlado]

In the latest versions, the VFB supports 3D LUT files, which can be used to do virtually any required color transformation.

Best regards,
Vlado

[Dave_Wortley]

Ok Great, next question, how to convert an ICC to a .cube file?

[vlado]

To answer that I need to know the format of .icc files... is it available somewhere? The format for .cube files is described here: http://doc.iridas.com/index.php/LUT_...s#IRIDAS_.cube

Best regards,
Vlado

[stellwagenc]

Hey Vlado,

i have this problem, too.

Here the render from Vray Framebuffer: http://www.3d-passion.de/problems/ro..._v02_test1.jpg
And here the render open in photoshop: http://www.3d-passion.de/problems/ro..._v02_test2.jpg

My monitor is calibrated with spyder3elite.

at the moment, i dont no what is the right rendering... i think the framebuffer ist wrong, but how can i test it??

[plastic_]

I'd like to be a able to embedd a ICC file to all images saved from the vray VFB.
Right now I have to manually assign my monitor profile in photoshop, in order to stay in a color managed workflow.

[plastic_]

assign the spyder(monitor) color profile in photoshop, don't use "convert to profile" but "assign".
then you can convert the image to srgb or whatever, it will have the same colors in ps and 3dsmax.

Hey Vlado,

i have this problem, too.

Here the render from Vray Framebuffer: http://www.3d-passion.de/problems/ro..._v02_test1.jpg
And here the render open in photoshop: http://www.3d-passion.de/problems/ro..._v02_test2.jpg

My monitor is calibrated with spyder3elite.

at the moment, i dont no what is the right rendering... i think the framebuffer ist wrong, but how can i test it??

[vlado]

From what I understand, ICC profiles are supposed to be applied globally in your Windows color management settings, rather than per application. Having each application use a separate profile just adds to the chaos.

Best regards,
Vlado

[stellwagenc]

the link in the first post http://www.artstorm.net/journal/2009...mut-dell-2408/ says all. now i unterstand it - at first, i don't unterstand it...

[plastic_]

They are applied per image. Images from a DSLR usually have either an AdobeRGB or sRGB profile embedded.
The problem is that images from 3dsmax are unprofiled. So if you got a monitor with extended AdobeRGB color space you have to embedd the right profile into the image somehow, otherwise it will be displayed as the system default, which is usually sRGB, with uncalibrated systems.
The only way to ensure that the color reproduction is constant between different monitors (and for printing), is that each image file has an ICC profile embedded.
Otherwise it's either over-saturated or under-saturated with randomly(?) shifted hue.

So what I'm doing now is assigning my monitor ICC profile to Vray renders, then converting it to a standard color space, like sRGB. That way it is clear that the image was created in my color calibrated environment.

For the global color management in windows, this ensures that the right ICC profile for the current display is used, that way you get constant results in viewing applications with proper color management support (firefox, photoshop, lightroom, after effects, windows image viewer, etc)

From what I understand, ICC profiles are supposed to be applied globally in your Windows color management settings, rather than per application. Having each application use a separate profile just adds to the chaos.

Best regards,
Vlado

[jow]

So what I'm doing now is assigning my monitor ICC profile to Vray renders, then converting it to a standard color space, like sRGB. That way it is clear that the image was created in my color calibrated environment.

I've been messing around with this problem lately and i'm finding if you start applying profiles (sRGB), the image in non colour managed programs is over-saturated, I E for example. Im getting far more uniform results across different PC's when leaving the image unprofiled.

[plastic_]

I've been messing around with this problem lately and i'm finding if you start applying profiles (sRGB), the image in non colour managed programs is over-saturated, I E for example. Im getting far more uniform results across different PC's when leaving the image unprofiled.

You can fix this by converting the image to AdobeRGB (or the calibrated spyder monitor profile) instead of sRGB before exporting it.
However, if you display the image now on a non-wide gamut monitor, in a non color managed app, the image will be under-saturated
There is no way to get colors shown correctly on every system, in every app, as long as there are 2 fundamentally different color systems for monitors (sRGB and wide gamut), and windows isn't universally color managing the whole UI. (Apple is even worse from what I heard)
For example, the firefox icon is yellowish orange on sRGB monitors and almost red on wide gamut (AdobeRGB) monitors.
For now, I recommend sticking sRGB for web, e-mail, etc., because it is more widely used. With print I never had problems with either color space, but when there is no color profile embedded in the bitmap, most printers/plotters will assume sRGB too.

[Morne]

I think we should profile for sRGB monitors since this is what clients ultimately have. We (graphics artists) are probably the only people having access to wide gamut displays (if we are lucky enough), everyone else has sRGB

[Tobbe]

Sorry to bring this old thread back to life, but this is getting really important. Wide gamut monitors are more common now and certainly used more in the industry. The framebuffer needs to be fully colour managed, use and respect the current monitor profiles! I'm still on XP but I don't think win7 does any "global" colour management either.

[vlado]

Well, you do have the ICC profiles; they are global for the entire system.

Best regards,
Vlado