ViewLayer - indirect only

HI. I want to isolate an object in an underwater scene. I am using a cube using the principle volume shader. When I choose indirect only to get only my thing with the volume effect, but without the volume, nothing happens. Is it because the book is not considered an indirect contributor?

Thank you

If I understand correctly, you are setting a volume object to “indirect only”, there is an object inside that volume and the volume is not affecting that object?

If that is what you mean, a little search tells me this is actually a bug. It is know from the developpers, has been known for a while and apparently has never been fixed.

https://developer.blender.org/T87916