Black fringe / poor AA for render elements when rendering with render masks

[braddewald]

When you want render just an object, and choose "selected objects" under "render masks" in the render settings, the main RGB pass looks great, but when you look at the render elements, there is a black fringe around the selected object you rendered. (3ds Max 2024, Vray 6.10.06)

[hermit.crab]

Could you simplify the scene and attach it here so we can troubleshoot?

[braddewald]

Attached. To recreate:

1) Render scene
2) Select teapot
3) Render settings > V-Ray > Image sampler (Antialiasing) > render mask > "Selected"
4) Re-render scene with teapot selected

When looking at the result, any Render Element (I only included the VrayDiffuseFilter and VrayLighting elements) includes a black fringe around the teapot. The RGB pass looks fine.

[hermit.crab]

Thanks for the report. I've logged the issue (internal bug-tracker id: VMAX-13334) for dev investigation. Not sure if there's another workaround except rendering the whole image.

[braddewald]

I think the problem is that it's using anti-aliased black and white masks. If I create my own aliased mask with only black and white pixels and load it up, it works great. Obviously it would be a lot easier to just use the built in functionality of selecting an object and pressing render...

[braddewald]

Any update on this?

[hermit.crab]

Not quite yet, I'm afraid.