ICC colour profiles have no effect

[kosso_olli]

When I load and assign an ICC profile into the frame buffer, I get strange inconsistencies in my workflow. I am forced to use the eciRGBv2 profiles, because the client demands it. I assign that profile to the frame buffer, and turn on the ICC button in the dropdown. The image is then saved to an .exr and loaded into PS CC 2014. As you can see, the image is way to saturated. I was expecting it to look exactly the same as in the framebuffer. Attached you can find the profile for testing.

Regards

Oliver



eciRGB v2.zip

[kosso_olli]

By the way, the backround for all this: I got two new wide gamut monitors. They were calibrated using a device, and since then the colors are messed up. Before I just assigned the sRGB profile to the images in Photoshop and they looked exactly the same, both in PS and Vray.

[vlado]

V-Ray applies the ICC profile only when displaying the image in the VFB. The saved image is still the original one. However you can copy the image to the clipboard exactly as visible in the VFB if you click somewhere inside the VFB image and press Ctrl+C.

Best regards,
Vlado

[kosso_olli]

Vlado, I know that. But when I apply the same ICC profile both in Photoshop and Vray, shouldn't the image look the same? That is what I did in the screenshot. Can someone from the supoort team please check if I am doing something wrong with the profile I supplied above?

[Morne]

You should check what your monitor is set to in windows. When you calibrated those monitors with a device, it should have been on the pc you are using. Each monitor would have IT'S OWN profile loaded into windows (because no monitor is 100% the same, even if they were manufactered one after the other). Max ignores these profiles because it doesnt support profiles. The VFB has its own built in support for profiles, if you specifiy a profile.

PS will read the monitor profiles, and from there will do it's best to translate to your specified eciRGBv2 profile.

Before, when you didn't have calibrated monitors, windows just enables sRGB and so from there it was much easier to get a match between VFB and PS.

[kosso_olli]

Okay, here is a screenshot from the color management in Windows. The profile specified is the measured profile for that monitor. So I assume that's correct. But what do I load into the VFB ICC correction? My monitor profile or the eciRGB that I have to use afterwards in Photoshop? Because either way, still no match... Is that because PS takes into account the measured profile from Windows and Vray/Max doesn't?



EDIT: I get an exact match, when I assign the sRGB to Photoshop and the measured monitor profile to the VFB ICC. Very strange... But how can I convert this to the demanded eciRGB without color shifts?

[vlado]

Is that because PS takes into account the measured profile from Windows and Vray/Max doesn't?

I think that's the case, yes. 3ds Max is not a color-managed Windows application, so the system ICC profile is ignored for it. Which is why you need to apply the ICC profile to the VFB explicitly. But Photoshop is a color-managed application and the system ICC profile is applied automatically.

Maybe you need to disable the system color profile and assign that in Photoshop manually too?

Best regards,
Vlado

[kosso_olli]

I can disable the system profile, yes. But I don't have an option to assign both the system profile and the eciRGB to Photoshop. Guess I will have to wait until 3dsMax gets proper color management like Maya with the last release...

[Mnietek2707]

I get an exact match, when I assign the sRGB to Photoshop and the measured monitor profile to the VFB ICC. Very strange

I think this is the difference:
Photoshop:
when you apply icc profile to image in photoshop, image is treated as created in color space described by this profile. And PS translate this color space to color space of monitor.
Color space of monitor is described by profile which is set in windows monitor settings. So: image profile -> monitor profile
When you assign sRGB to image in photoshop conversion looks like: sRGB -> monitor profile

VFB
I think Vray assumes that image is in some kind of linear sRGB color space and after assigning some profile there is conversion between this linear sRGB -> assigned profile
When you assign monitor profile in VFB settings conversion is the same like in photoshop: sRGB -> monitor profile

this is my theory
________
sorry for my English

[Morne]

What I know about profiles I learnt from Jeff Mottle over at http://www.thecgschool.com/
Maybe contact him and get his opinion. He's very knowledgeable on the subject of color management and profiles.