Volumetric pass black

[mtanasiewicz]

When I hit "render only elements" my volumetric pass renders completely dark. But when I render with beauty it is ok.

[mtanasiewicz]

Hmm... Actually all my render passes return black, after hitting "render only elements"... But with beauty pass everything is ok. Maybe I'm doing something wrong? Corona 1.2.1

[Ludvik Koutny]

Hmm... Actually all my render passes return black, after hitting "render only elements"... But with beauty pass everything is ok. Maybe I'm doing something wrong? Corona 1.2.1

Render passes only feature is limited to simple passes that do not require raytracing, like masks, normal pass, world position pass, etc...  It does not work with passes that require beauty pass to be computed.

It renders render passes instantaneously, but only because those passes do not require beauty to be rendered.

[mtanasiewicz]

OK, I didn't know. Is there any way, I could render my volumetrics pass to compose it later in photoshop without baking it to beauty and rendering 2 times same image? I didn't find any information on that.

[Ondra]

ok, this is not a bug. Although I will add a warning when "render only elements" is used incorrectly (without any elements that could get rendered)

[maru]

OK, I didn't know. Is there any way, I could render my volumetrics pass to compose it later in photoshop without baking it to beauty and rendering 2 times same image? I didn't find any information on that.

No, this is not possible. As Ludvik wrote, only some elements can be rendered without full beauty pass.
However, you can disable some unused features to make rendering very fast (especially if you are using "single bounce only" for the volumetrics). Reduce max ray depth to minimum, disable secondary solver, etc. You can also apply a 100% black material to everything (or use override mtl) and leave only lights and the volume mtl.

[mtanasiewicz]

OK thank You. I knew this way from Vray, but I hoped there is a faster solution :D Will keep it that way.

Best regards