Hello and ACES 3D Gamut question

Hello everyone,
So happy to join you and eager to learn ACES for my art.

I’m currently a French student in Cinema and Digital Art.
Of course, we stick to REC709, and spoke about REC2020, my curiosity did the rest to discover ACES :slight_smile:
It totally makes sense to me to have a future-proof reference englobing all the color spectrum (and beyond), deal with linear gamma of 1, and provide IDT and ODT to adapt to input and output devices, so I updated my favorite 3D software to deal with ACES.

As a 3D artist, I found it fun yesterday to explore and quickly make a rough draft of the 3D gamut of sRGB


Just an artistic point of view missing multiple aspects for now.

Now I wonder if there is a 3D gamut representation for ACES.
I know the middle section of the shape is the triangle and one angle is in negative values, which is a great discovery (and mind blowing for me).

What about the Luminosity axis?
Does the shape follow the sRGB one (more yellow in high values, more blue in low values)?
Does HDR influence the shape itself?

Yeah, now these are the questions I have on week-ends. I love this. Thank you!

Have a great day :slight_smile:

1 Like

Welcome @philm,

We have an online tool that can help you compare gamuts in various models here: https://www.colour-science.org:8020/

So here you have sRGB vs ACES2065-1 in the CIE L^*a^*b^* colour model:

Given you are using Blender, here is some code that was working a few years ago to generate 3d gamuts there: Colour - Blender · GitHub, from there you can export to gLTF & co: colour-science - Trying glFT 2: sRGB Colourspace Volume in... | Facebook

Cheers,

Thomas

1 Like

Thank you very much Thomas!
That’s exactly what I was looking for.

I thought ACES2065-1 was a triangle.

About the blender script, this is great, unfortunately, it doesn’t work anymore, I would have to install a 2017 version to try. I don’t think I’d be able to adapt it to the new Blender (python 3 since 2.8) though.

It is defined as a triangle in CIE xy but as soon as you convert it to another colour model and especially a 3D one, its shape will change.

It should not be too hard to update, won’t have time soon though, but could if I don’t forget in the coming weeks.

Oh, ok, then I need to study more :slight_smile: