Volume AOV not rendering

[Anonymous]

Hey guys, having an issue with atmosphere shader not rendering to AOV. I mentioned this issue in previous Arnold core, but it's still the same in new Arnold. I'm trying to create a volume path with atmosphere shader, it's visible in driver_c4d_display, but it's totally black and empty in EXR or Tif. Any ideas?

[peter.horvath6V6K3]

It's still a limitation. The atmosphere shader and the volume are different implementations and the atmosphere shader does not contribute to the volume AOVs. The workaround is to use a scaled Arnold Volume in box mode instead of the atmosphere shader.

[Anonymous]

Ok this makes sense, thank you. But it's visible in c4d_diplsay, why it can't render same to aov?!

[peter.horvath6V6K3]

What do you mean by it's visible in c4d_display? If the AOVs are in the Picture Viewer under the Layer tab correctly then they must be written to disk properly with the native Save option, or using Arnold drivers. Don't forget to setup the AOVs for each Arnold driver.

[Anonymous]

Atmosphere was visible in volume aov in previous Arnold core. Now it's not. I'm trying to follow your advice, but the result looks completely different with box volume

[Anonymous]

Peter, do you think is there any chance to output atmosphere to aov?

[peter.horvath6V6K3 · Accepted solution]

Right, it was changed in Arnold 5 when the closures and light path expressions came in. Actually as I see the atmosphere is in the emission AOV but can not be (easily) separated from surface emission at the moment. We'll take a look if the workflow can be improved in a future release.

[Anonymous]

Yes, it's such a vital need! Looking forward for an update.

[Anonymous]

Yes, it's such a vital need! Looking forward for an update.

[brurpo]

Yes, having the Atmosphere and Surface emission in the same AOV is terrible for post-production and broke our workflow.

Please fix this!

[lamarKPDHG]

Bump. Is this being fixed anytime soon?

[peter.horvath6V6K3]

I still don't have an ETA, sorry.

[Anonymous]

Maybe there is a way to mange the issue using the Leght Expressions?

[peter.horvath6V6K3]

It's not possible to separate the atmosphere in a light path expression either currently, as far as I know.