Cryptomatte and progressive rendering?

[DHX_Richard]

Hi Guys,

Currently we're gearing up to run a production test of vray 3.6 and notice that cryptomatte doesn't appear to support progressive rendering


Currently we're gearing up to run a production test of vray 3.6 and had intended to use cryptomatte in conjunction with time/sample based resumable rendering with denoise. This combination doesn't appear possible at this time "// Warning: V-Ray : Cryptomatte is not supported in progressive mode and will be disabled. // ". Can you advise whether this is a design choice or a temporary limitation?

Thanks
-Richard

[yolov]

As far as I've discussed this with the developers, it will be quite complicated to make it work for progressive. There's some work being put on that, so it might be possible in the future.
For the moment, though, I'm afraid it's a limitation that can't be worked around.

Hope this info helps.

[DHX_Richard]

Thanks for the quick reply Yolov!

I'll put it to my team to see whether cryptomatte or resumable rendering is more important.

Related we are there any issues of generating a second "mattes pass" with no lights and enforced minimum sampling in use with a cryptomatte pass? I'm thinking something similar to what do to generate a reflected / refracted mattes pass?

Thanks
-R

[yolov]

You could do a second pass for just the matte masks with cryptomatte, just like you would do it for multimattes, i.e. disable GI, disable lights, disable material maps, reflections, refractions, SSS etc, but keep the image sampler settings unchanged.
This basically means going to render settings > Overrides tab and disabling (almost) everything in the Lighting, Materials and Textures tabs, while everything in the Camera and Geometry tabs remains the same.
The only consideration to make in such a case would be directly visible lights that have geometry (dome, rect, sphere and mesh lights for which the "invisible" option is disabled) since they are included in the masks.

[Fredrik Averpil]

The problem with setting up a second pass for cryptomatte is that the AA wouldn't match up with a nice progressive beauty render if you flat-shade and turn off all lights etc for the cryptomatte pass.

We're completely won over on cryptomatte at the moment and this currently stops us from using progressive rendering on a regular basis, unfortunately.

EDIT: Not saying we're requesting cryptomatte in the progressive renderer, just that we really, _really_ like cryptomatte. I think if we would consider resumable rendering for a project, we'd have good reasons to opt out of cryptomatte and the trade-off would not be especially dire, as there's huge benefits to resumable rendering on certain projects ...whereas on quickly-paced common projects cryptomatte saves a lot of time just in general.