3ds max 2024 OCIO - Automatic colorspace assignment

[^Lele^]

Have you got a stable build installed?
It works perfectly fine for me with the latest.

EDIT: the oversaturation may be due to how the material editor is set up: with aces, you get the aces ODT in there by default, so, more contrast.

[JonasNöll]

Yeah, I got V-Ray 6 Update 1.1 (6.10.06 build 00000) that should be the one from the official download section.
Strange, I also had the feeling it was working earlier, but then I switched back and forth manually between the (3dsMax Colormanagement) and the (3ds Max Gamma Workflow + Manual ACEScg in V-Ray) a couple of times and now I get identical results even my VRayBitmaps are set to Default and I use an sRGB .jpg in the diffuse. In both cases I have to manually set the Primaries to sRGB.
I will check a bit more and maybe post some example image if I don't manage to find whats wrong. Just wanted to clarify if the 3dsMax Colormangement SHOULD in theory also influence the VRayBitmaps behavior.

[^Lele^]

Just wanted to clarify if the 3dsMax Colormangement SHOULD in theory also influence the VRayBitmaps behavior.

Insofar as choosing the expected RGB primaries for the loaded map, yes, it most definitely does (with the caveat of having to set Max up properly).
For the Color Space Transfer Function (i.e. the gamma), only if it's set to "from 3ds Max" (notice that this, in general, will always apply an sRGB/2.2 inverse gamma to incoming LDR maps. be wary.)

[JonasNöll]

Insofar as choosing the expected RGB primaries for the loaded map, yes, it most definitely does (with the caveat of having to set Max up properly).

So shouldn't in this case the rendered images look slightly different for the orange object when the RGB primaries are set to Default? If I understand correctly when using traditional 3ds Max Gamma workflow it would assume the jpg to be ACEScg (because no nametag is present) and with 3ds Colormanagement it would assume the jpg to be sRGB or? But they look exactly the same.

[dlparisi]

wish it was obstinacy holding us back.

I don't...I hated that discussion in a lot of ways. At the time I remember thinking that this was exactly the opposite of the response we'd get from Chaos.

[^Lele^]

So shouldn't in this case the rendered images look slightly different for the orange object when the RGB primaries are set to Default? If I understand correctly when using traditional 3ds Max Gamma workflow it would assume the jpg to be ACEScg (because no nametag is present) and with 3ds Colormanagement it would assume the jpg to be sRGB or? But they look exactly the same.

There is no difference currently about untagged images, be it under max or v-ray's dominion.
It looks like that texture's being misinterpreted (assumed to be ACES but being sRGB) in both cases.

[^Lele^]

I don't...I hated that discussion in a lot of ways. At the time I remember thinking that this was exactly the opposite of the response we'd get from Chaos.

I remember thinking just the same at the time, i was at Mackevision in Stuttgart when I read it.
I meant my sentence as a hyperbole: if it only were obstinacy, we could fix it easily.

[JonasNöll]

There is no difference currently about untagged images, be it under max or v-ray's dominion.

Ok, I'm really confused now as this seems to me not really consistent to what you said before. Why would it matter if its tagged or not. If its not tagged V-Ray will always assume it to be in the the colorspace that is selected in the renderglobals.
So if I use 3ds Max Gamma + ACEScg in the VRay settings then it should always assume the jpg is in ACEScg, UNLESS it's tagged.
While in 3ds Max OCIO Color Management it should assume the jpg is in sRGB as defined in the Colorspace Assignment Rules.

So in this case it should give 2 different results. But it seems in both cases the jpg is assumed to be ACEScg. So the conclusion would be that V-Ray doesn't respect the Color Space Assignment Rules from 3ds Max

[^Lele^]

You are confused.
Gamma != color primaries.
Max does nothing about those to bitmaps.

[JonasNöll]

Ok, right here I should probably give up on trying to understand what you want to say with these cryptic replies that don't seem to have anything to do with what I want to know

[kosso_olli]

I remember thinking just the same at the time, i was at Mackevision in Stuttgart when I read it.

Those were fun times! Still remember sharing the office with you for a few weeks, learned quite a lot!

[kosso_olli]

Ok, right here I should probably give up on trying to understand what you want to say with these cryptic replies that don't seem to have anything to do with what I want to know

Gamma != color primaries.
Max does nothing about those to bitmaps.

What Lele means here is that Gamma is not color primaries. And he's right on this point.

[^Lele^]

Ok, right here I should probably give up on trying to understand what you want to say with these cryptic replies that don't seem to have anything to do with what I want to know

I noticed i can't help.

[JonasNöll]

What does this have to do with anything that I asked or said? Let's break it down:

1. You said VRay follows 3dsMax 2024 Colormangement Rules
2. 3dsMax 2024 Colormanagement Rules define that all jpgs are assumed to be sRGB
3. I demonstrated that this is not the case. BOTH jpgs in my example are interpreted to be in ACEScg, in 3ds Max 2024 (with new Colormangement where jpgs are assumend sRGB following the Colormanagement Rules) and 2023 or earlier (without new Colormangement where jpgs are assumed to be ACEScg by V-Ray). It gives the same result.
4. My question: Why it gives the same result given that it SHOULD follow the Colormangement rules as claimed?

Just please answer this question in a logically followable way. Maybe I'm too stupid, maybe I'm doing something wrong, that's no problem. If it turns out I do some mistake I'm very happy to learn - really! Just please describe it in a way that answers this question.

[Mr.Mxyzptlk]

Is this something that could work temporally?

https://forums.cgarchitect.com/topic...y-and-3ds-max/

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