Rectangular lights set to invisible showing up in Object ID pass

[pieter_gaerdelen]

Hi there,

I'm trying to create a pass with the Object ID render element, for compositing purposes.

For some reason the 'Light rectangles' in my scene are interfering with the masking of the objects even though they are set to invisble in the scene.
Same with Sphere-lights actually.
Can't remember this happening in earlier version of Vray.

Am I missing something here?

Much appreciated.

Pieter

[pieter_gaerdelen]

As a workaround I've tried to do a seperate render with no lights to get the Object ID pass.
Works just fine and it's obviously very fast, but the anti-aliasing is so poor it's unusable for compositing.

[pieter_gaerdelen]

It seems to be down to the refractive nature of the material of the back wall.

[aleksandar.kasabov]

Hello pieter_gaerdelen,

Apologies for the delayed reply.

Would you mind sharing a test scene with us so we can have a look? Upon testing on my end (with refractive material on the back wall) I was not able to reproduce the issue. Also, please specify the exact versions of V-Ray and Cinema4D that you have installed. Thanks.

[pieter_gaerdelen]

Hi Aleksandar, thanks for looking into this.

I'm guessing it is down to the SSS?
Please find a simplified version of the scene attached.

I'm running C4D release 2023.1.0 on a Mac running Big Sur 11.7.1.
Vray 6 for Cinema 4D, hotfix 1 (v6.00.02 from Dec 6 2022).

Thanks in advance.

[aleksandar.kasabov]

Hello pieter_gaerdelen,

Thank you for providing those details.

I had a look at your scene and it seems that the issue is not caused by the SSS but by the opacity of the material. I have reported it to our developers for fixing (bug ID: VC4D-1669) and I will let you know once we have an update on the matter.

A workaround to that would be to change the opacity of the object via the Visibility option in the V-Ray Object Properties tag. Keep in mind that a limitation there would be that you cannot use a map (as in your case) to change the opacity and you can only set a percentage. I hope this is of help.

[pieter_gaerdelen]

Hi Aleksandar,

Thanks for the time and effort taken to look into it.
Also, thanks for the suggested workaround with the visibility option in the Object Properties tag.
I wouldn't have thought of that as a solution.
We all should probably use it more often than using opacity in the material settings (with the percentage limitation in mind).

Managed to work around it with a seperate render pass with no materials. Took some extra time and compositing, but managed to get the work done in time.

Anyway, glad to hear, a fix is being looked into by the developers.

Regards,

Pieter