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Hello all,

Finally end of the year so I have some free time to write about the issues I noticed, and to ask some of you to enlighten me about the workflow from Octane Maya to AE or PS, because clearly I am doing something wrong.
So I have been using Octane from its very first days (8 years now for me), and I since I was always dealing with projects that require accurate color representation I never had issues, what I see in Maya Octane viewport was always what I am getting as an output.

Now comes the BUT part. Since I noticed that Octane has ACES as default preview (not sure which version it was) my output suddenly became so different from what I see that I need to do heavy color corrections to come close to what i see in Octane but colors are way less saturated and contrast is lost from the renders. To be clear, I am not using ACES, I am switching it back to sRGB in the viewport while working on lighting and shading, but that sRGB output vastly differs from what I see in viewport and what I am getting in AE or PS when reading the EXR 16bit float files. Did something change in the color science with octane when ACES was introduced? Or I am just doing something very wrong? For the past 8 years I never had an issue with mismatch between the viewport and output EXR files, so this is very annoying now and really impacting our work.

Hope someone can help and advise Happy new Year!

Braca wrote:Hello all,

Finally end of the year so I have some free time to write about the issues I noticed, and to ask some of you to enlighten me about the workflow from Octane Maya to AE or PS, because clearly I am doing something wrong.
So I have been using Octane from its very first days (8 years now for me), and I since I was always dealing with projects that require accurate color representation I never had issues, what I see in Maya Octane viewport was always what I am getting as an output.

Now comes the BUT part. Since I noticed that Octane has ACES as default preview (not sure which version it was) my output suddenly became so different from what I see that I need to do heavy color corrections to come close to what i see in Octane but colors are way less saturated and contrast is lost from the renders. To be clear, I am not using ACES, I am switching it back to sRGB in the viewport while working on lighting and shading, but that sRGB output vastly differs from what I see in viewport and what I am getting in AE or PS when reading the EXR 16bit float files. Did something change in the color science with octane when ACES was introduced? Or I am just doing something very wrong? For the past 8 years I never had an issue with mismatch between the viewport and output EXR files, so this is very annoying now and really impacting our work.

Hope someone can help and advise Happy new Year!

Hi Braca,

Happy New Year and thanks for the post.
Yeah, we have introduced White Light Spectrum option in Octane Kernels>>Color rollout that controls the appearance of colors produced by the spectral emitter(eg, daylight and Blackbody emitter) and Color Space node for image texture nodes. In Maya, we have to attach the Color space node manually depending on our workflows.
Please try setting the White light spectrum as Legacy/flat from the drop-down and see if it matches the output.

Have a great day!


cheers

Thanks BK, will check it out. I missed this whole White Light Spectrum and Color Space Node introduction.

Braca wrote:Thanks BK, will check it out. I missed this whole White Light Spectrum and Color Space Node introduction.

Hi Braca, I've wrote two pages about the topic of this thread, if you are interested: Octane Color Management & Octane ACES.

Braca wrote:(...) that I need to do heavy color corrections to come close to what i see in Octane but colors are way less saturated and contrast is lost from the renders.

Not any sort of "manual correction" is required. It's actually a red flag if this is occurring. "Color Management & Post", creative intent aside, is technical, aka "correct or not correct", simply said.

Braca wrote:To be clear, I am not using ACES, I am switching it back to sRGB in the viewport while working on lighting and shading, but that sRGB output vastly differs from what I see in viewport and what I am getting in AE or PS when reading the EXR 16bit float files.

That's fine, but (the introduction part).

Thanks Elsksa,

will try to find time to read through it.

So i finally managed to get somewhat similar output in the octane viewport and AE, still not 100% the same but it is close.
However this is a test I did with flat lightning and pure diffuse material and as a texture i got some pantone color samples and did a separate color check in PS and matched the colors with 100% accuracy.
So the RGB and hashtag values of the colors in the image are correct.

However when I do all the necessary conversion in AE, and it is indeed matching the octane viewport somewhat, the whple rendered image is way off in saturation and brightness check the attached image.
More strange is when I put diffuse color values exactly like provided RGB values in Octane RGB spectrum texture they are looking completely washed out.

Let me know what am I missing.

ACES and ("display") sRGB (not just "RGB") is expected to be dissimilar. ACES is a vastly different color encoding system.

Be aware though, I've mentioned it on the links I've shared and other forum replies, ACES is dispensable and undoubtedly not an absolute necessity. Just a thought to keep in mind. The ACES write up by Chris Brejon is a strong recommendation (warning, deep rabbit hole ahead).

Yeah I understand that, I do not want to use ACES, problem is when trying to work with the standard workflow results are even worse. Because now Octane defaults to ACES in preview window.
Really not sure what workflow to use to ensure proper colors and to get what I see, or to be somewhat close in comparison.

But also a big question about the RGB Spectrum Texture in Octane, why it is so off with correct rgb values put in? This was a problem even before ACES

Braca wrote:So i finally managed to get somewhat similar output in the octane viewport and AE, still not 100% the same but it is close.
However this is a test I did with flat lightning and pure diffuse material and as a texture i got some pantone color samples and did a separate color check in PS and matched the colors with 100% accuracy.
So the RGB and hashtag values of the colors in the image are correct.

However when I do all the necessary conversion in AE, and it is indeed matching the octane viewport somewhat, the whple rendered image is way off in saturation and brightness check the attached image.
More strange is when I put diffuse color values exactly like provided RGB values in Octane RGB spectrum texture they are looking completely washed out.

Let me know what am I missing.

TestColorMAtch copy.png

Hi Braca, could you upload a copy of the test scene you are using, ideally exported to ORBX format? That would be very helpful to figure out what's going on.

Also, when you say "properly converted in AE", exactly what conversion are you doing? There are a few different things that could potentially be considered "proper".

Hey Karu,

I mean nothing much is happening in the scene, just putting RGB image onto a plane with diffuse material, RGB image into the diffuse channel (I also tried with emission, exactly same results) and making the environment all white with the value of 1.
In this scenario the original RGB image should more or less match with the render output, and I can confirm that same setup in C4D actually gives the desired result. IN maya however it is completely wrong, and I think it has something to do with the IPR render preview.
As for the setup and conversion of ACES in Maya and AE I am using this steps:
https://docs.google.com/document/d/1ZlV ... sp=sharing
This is a document I have put together from some sources, just like a reminder what I need to set up.

Maybe this steps are wrong.