"Problem" with EXR files

[italocampanelli (Ítalo Campanelli)]

Hey! I’m having a problem saving my Arnold renders to EXR. The exr file doesn’t match at all what I see on Arnold render view. The colors are completely off, but when I save my render as a PNG, the image is perfect, exactly like I see on the render view. For example. The top image is the image saved as PNG and the bottom one is the one saved as EXR. the png one matches perfectly what I see on the render view. I’m trying to open the exr files with after effects and photoshop. maybe I’m missing some step on these programs?

[ChrisBrejon (Christophe Brejon)]

Hello Italo and welcome !

I guess your issue is not with the exr file itself but with the way you view/display it.

When you save an png file, you probably burn the ODT in it (display-referred values). On the opposite, when you save an exr file, values are written as scene-referred. The bottom exr file seems to be displayed with a simple sRGB transfer function instead of an ACES ODT).

So when you import an exr file into Photoshop or After effects, you need to display under the same conditions than in Arnold. Issue is there is no (official) OCIO integration in those softwares.

You have a couple of solutions though :

• You could use a non-commercial version of Nuke (which is free to download).
• Or try the OCIO plugins for After effects and Photoshop.

We discussed in a previous thread about After Effects :

ACEScg doesn't match in AfterFX

Thanks, also seems like i have another issue, don’t really know how to export it for Web from Nuke ( or export from Nuke to PS/AAE/Lightroom etc ). Also this method doesn’t work for AAE ( won’t work with Photoshop then too ). An Idiot’s Guide to ACES: “Before writing final images to disk, use the OCIOFileTransform node to convert your comp into the appropriate delivery color space. See the “Fusion” section above for hints on what color space you might want to write to.” Hmmm. [21c5191753073…

And here is a tutorial for Photoshop :

Comping ACEScg renders in Photoshop - Chaos Forums

Hope this helps,

Chris

[italocampanelli (Ítalo Campanelli)]

hey! thank you a lot! I tried downloading the OpenColorIO plugin for After Effects, but none color profile I chose worked ): I had seen this After Effects topic before I post here, just in case someone had the same problem. But this photoshop one I hadn’t seen. I’m going to try it now. Thanks!! Btw, you’re the one who wrote that book on Aces, aren’t you? I read all of your texts about it

[TooDee (Daniel Brylka)]

Hi Italo,

can you elaborate on your workflow a bit more?

Your question seems more about a view transform in general than an ACES specific question.

Greetings

Daniel

[italocampanelli (Ítalo Campanelli)]

Hey, Daniel! Yeah, you’re right, Chris Brejon told me that. I downloaded and installed the Photoshop plugin OpenColorIO and managed to get the correct result, but I still didn’t get to find a way of viewing the correct colors in After Effects, which is the one I really need to use I don’t know how to use Nuke

[Shebbe]

Hey Italo,

Have you looked into this tutorial? It should help you set up your AE project correctly and should also apply to your EXR files.
Also don’t forget the thing he mentions in the description for your exports ;).

ACES linear workflow using OCIO in After Effects