Docs on using ACES in Vray 5

[KristinIvanova]

Hey Morne,

We are working on it.

Cheers,
Kristin

[matthew999]

+1 on this, it is necessary to add it to the thread
It is something that people do wrong on getting started with ACES

Hi Muhammed_Hamed

if i have a 32bit hdr that is srgb when opened in photoshop, what colour space should i set the file texture node? utility raw or utility srgb - terture?

thanks matt

[Muhammed_Hamed]

Hi Muhammed_Hamed

if i have a 32bit hdr that is srgb when opened in photoshop, what colour space should i set the file texture node? utility raw or utility srgb - terture?

thanks matt

Utility Linear Srgb
Your HDRI uses a linear transfer function, and photoshop applies an sRGB curve on top to view it correctly
On the other hand, Utility RAW means no conversion is done (it is uses for roughness maps, normal maps...etc)
and Utility sRGB texture, is for 8 bit file formats like JPEG or TIFF (Albedo maps or any color channels).. it is because these files have an sRGB transfer function (burned to them)

Hope this helps you out, let me know

[KristinIvanova]

Hey guys,

Here is the guide for ACEScg worfklow in V-Ray for 3ds Max: https://docs.chaosgroup.com/x/HZv5Aw

Cheers,
Kristin

[Muhammed_Hamed]

Looks pretty good!
Thank you

[matthew999]

My workflow is to use the hable preset and play with the curve until I get something that I like(instead of using OCIO in the frame buffer)

6-About this part,

Hi Muhammed_Hamed

Am I correct in doing the following?

in VFB
1- Switch from ocio to sRGB in Display Correction
2 - use filmic tonemap, set the tone mapping space to ACEScg with hable preset?

It seems to work and I get much more control over tonemapping than the over crunched blacks of aces.

Now I'm having trouble trying to get anything that resembles my render into photoshop but that's another story

[Muhammed_Hamed]

Hey matthew999
You are correct sir, this way you are creating your own Output Transform, you can adjust the curve to your liking.
Another way that people use, is load OCIO in the frame buffer and using the default ACES sRGB view transform. But you don't have control over the tonemapping in this case.

The ACES sRGB view transform includes colorspace mapping from ACEScg working space to Linear sRGB and tonemapping to expand mid-tone contrast and compress shadows and highlights

This is what you should use if you are willing to get a prefect match between the frame buffer/Nuke/Photoshop..etc

A third way is to set Display correction to none, and use a filmic tonemapping layer.. set the tonemapping space to ACEScg, and use the AMPAS preset. This is supposed to match the ACES sRGB view transform(but it is not a perfect match so far and they need to fix it)

And I have a detailed thread about the Photoshop workflow, it will be helpful to you

[matthew999]

Hi Muhammed_Hamed

Thanks for your return my good sir

yes i am following this thread

https://forums.chaosgroup.com/forum/...op#post1085437 and its very usefull

I Really like the filmictonemap result but atm there is no save to LUT in VFB so i cant recreate what i see in VFB successfully in photoshop using multilayer exrs. Such a shame