Cinema4D in an ACES workflow

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Hello,

I have managed to get a good ACES workflow going in our small company. From ingest over compositing to grading and archival everything works pretty good.
The last missing bit in that workflow is Cinema4D. Has anyone a good solution for that?

The only way I can think of is the possibility to use custom viewing ICC profiles in the application.
So I tried to make those using OpenColorIO in Aftereffects. But whatever transform I write to a ICC profile there, delivers visually wrong results in Cinema4D.

3D-Rendering is no problem. I render OpenEXR files, which are always sRGB/linear, which can easily be matrixed to ACES AP0.
But when put through the RRT/ODT, of course, the look changes.

So I need to have a “live” viewing RRT/ODT transform for the Cinema4D editor. And that should be possible through a viewing ICC-Profile. Isn’t it?

Anyone else tried that or has some tips for me?

Thanks!

Peter

Sorry to drag up this old thread, but I’m trying to figure out similar things with C4D. As far as I can tell it doesn’t have much in terms of robust color management.

Did you end up figuring anything out?

No, nothing has changed. I can ony see a sRGB picture in Cinema4D and have to see what it will look like through tha RRT/ODT. A little workaround is to setup an ACES RRT/ODT Project in Afterefects and the render to the same filename in Cinema4D. Then you can switch to AE and get a RRT/ODT Preview. Far from a good solution. But at least a solution.

I tried to convince MAXON to have a look into ACES. But they say then have no idea what this is at all And obviously they are not interested to get informations about it.

If anyone has a solution to that, maybe through ICC profiles, I would be still very interested.

Peter

Not with plain Cinema4D, but I have recently been experimenting with a method for previewing an approximation of the RRT + sRGB ODT in Cinema4D using the Octane Render plugin.

It is very experimental, but if any Octane Render users want to contact me directly, I would like to have a few people test my method.

Hi Nick, I noticed your post about ACES with C4D Octane. It was a little while ago and wondered if you have progressed with any solutions. I am getting interested in ACES due to using DaVinci Resolve, Photoshop C4D etc and want to get to a point where I can have a workflow using ACES as my pipe.
Thanks
Chris

Hi @chris.conway. Unfortunately the testing of my C4D method was stalled because it relies on the LUT support which is only in Octane Render v4. I understand that when v4 stand-alone was released (some time back) the beta of the C4D plugin was discontinued, but as yet there is no release version. It’s out of my hands!

Hi Nick, thanks for getting back so quickly. I am using Octane 4 for C4d on PC with the RC5 version and have had no problems. there was a short period when RC4 stopped and RC5 started.

Here is the download link

Thanks
Chris

Hi Nick,

Any news or progress with your method for this? Would love to test it out!
Was doing a composite with linear EXRs onto Drone Footage (inspire 2, zenmuse) and really struggled matching them up.

I don’t think the DJI idt’s are available yet either. But would be awesome to have a good output from C4D Octane!

Informative thread…!!

Hello Everyone :slight_smile:

I just found, that the Redshift-Renderer (which is now owned by MAXON and therefore gets special attention in Cinema4D) offer OCIO in it’s preview called “Redshift RenderView”. Thats great! Seems to be at last a first step for Cinema4D to join the ACES family.

From my testing with the demoversion I got a feeling, that there is one big implementation problem. I can only eyeball it, but at the same time I think it’s a logical assumption:

It seems to me, that all Rendering is still done in sRGB and linear. Like it always was. The OCIO is then just put ontop of that. So if I load the OCIO ACES-configuration and select a view transform in the Redshift RenderViewer, it takes what it gets from Cinema4D (which I assume is sRGB linear) and handles that as if it would get real ACES-Data. Don’t know AP0 or AP1.

All those setting reside in a menu called “Color Management”

BUT there is another menu-section that is called: LUT
There is also a promising checkbox there called: “convert to log space before applying LUT”.

Right now I am still testing and trying really hard (for years now) to get a usable ACES workflow in Cinema4D.
I just wanted to let you know that it’s there in RedshiftRenderer for Cinema4D and maybe you want to join me again in finding how we can do that.

Thanks!

Peter

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Hey Peter!

Awesome, let us know what you come up with! I found the same options in the camera but couldn’t figure out how to get it working.

If i find some more info on how to get it working ill post it here!

Alex

Hi, I’ve had more of a play with C4D and Octane (a bit of Redshift). I think Peter is right that Redshift is still using sRGB Linear internally, the LUTs are surface covering only.

In Octane I have set C4D to Linear workflow.

My Octane Settings are:

Camera Imager
Response sRGB, Natural response ticked on, Gamma 1.

In the render settings I have.
Main
Render Buffer type - Float Linear.
Render Passes
Image colour profile - Linear
Tonemap type - Linear

Davinci Colour Management
Color science - Davinci YRGB Color Managed
Input - Linear
Timeline Color space - sRGB
Output - sRGB

I am getting the exact same RGB colours back in Davinci as I put in my Octane Material in sRGB (The WB is slightly off but I think it is because of the lighting temp 5750 that is in my lights) Once I do a white balance the numbers are correct.

I would be happy to get any feedback on this. It seems to have worked.

Chris

Hi all :slight_smile:

After a long break with that topic, I think I finally figured out how it works.
And as I found 2 Youtube tutorials, that (in my opinion) get this completely wrong I think I have to explain my way here.

As I always suspected Cinema4D is sRGB linear. And there is no way to change that at this moment in time.

The Redshift IPR applies the transforms of OCIO to anything it gets from Cinema4D as if it was ACEScg.
That’s basically it. That means that all shaders that you build are: The numbers you enter but in AP1.

So for pure creative work you see what you get when you look throught the RRT/ODT that the IPR shows you. What you see in the colorpicker of the Cinema4D-Interface is wrong.

Textures and footage you use therefore have to be converted accordingly. That can even also mean a reverse RRT/ODT.

So for example if you have a 8-Bit-Texture that you want to exactly keep it’s look through that pipeline would mean for example in Aftereffects (with OCIO Plugin):

8-Bit sRGB-Picture > Convert from Output sRGB (OCIO) to ACEScg > Save as OpenEXR 16-Bit float > Import into Cinema4D-Shader-Graph for Redshift.

This way you get what you saw :slight_smile:

Yes, it is cumbersome. But at least it’s possible. And I finished a few jobs with this pipeline.
A real tricky thing is to match a certain color like a company logo. But I think you all now can figure out yourself how this is done. Probably with a converted reference texure you try to match or somethink like that.

So please let me know if you can confirm this workflow or please enlighten me if I got something wrong :slight_smile:

Peter

Hello Peter, thanks for the update.
This looks alright to me even if I should mention that the conversion process you are showing should only be used for logos and client’s brands. Not for actual textures.
This topic has been detailed a few times on ACESCentral and using the ODT as an IDT should only be used for non-PBR elements.
Here is a link I found very interesting : Utility-srgb-texture too dark Hope it helps !

Regards,
Chris

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Thanks Chris,

so what is the actual conversion process? I almost never used the Utility things io OCIO.

So for example if I have a simple 8-Bit sRGB Texture:
I convert from Utility - sRGB - Texture to what? To ACEScg?

So in Photoshop I would have to change the 8-Bit Texture to 32-Bit. Then it’s already sRGB linear. And then use the Utility - linear - sRGB to go to ACEScg?

But in any case the final look would be different, because that doesn’t compensate for the RRT/ODT.

Could you explain the conversion steps, please?

Thanks!

Peter

Hi Peter,

I wrote a little piece also about this topic. Maybe you find this helpful.
You can find it here:

Best regards

Daniel

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Thanks @TooDee and @Peter_Rixner ! We are about to update the Knowledge Base with an article on this topic. Meanwhile, you can check those related threads :



For conversion, you could give a try to this tool :

You can download it for free and even give feedback to its developer @MrLixm.

Basically most users would complain about their albedo textures being too dark when displayed through the ACES OT. But good news is that the OT also allows artists to use lights with an energy much closer to real life (aka way higher), allowing for a better GI and a more realistic behavior for PBR renders.

Hope this helps (a bit),
Chris

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