VRayEnvironmentFog affected by Vray Rectangle lights set to invisible

[CrimsonKing]

Hello
I'm trying to resolve the problem with the incorrect VRayEnvironmentFog render
It looks like some of the Vray Rectangle lights set to invible and excluded from generating EnvironmentFog are still present in the VRayEnvironmentFog.
The output image looks incorrect. There are outlines of these lights (with different sampling) in places where the vray lights are in the scene; see screenshots

The similar problem is with the Cryptomatte pass. Some of the Vray lights (set to invisible) are present in the cryptomatte pass and they are covering other objects so the cryptomatte pass is useless .

Don you have aby ideas how to solve these issues ?

Kind Regards
Greg

[Martin.Minev]

Hi,

The invisible V-Ray lights being visible when using V-Ray Environment fog is a known bug. Will increase the priority of it.
Regarding the Cryptomatte pass, this should work in the latest official V-Ray Next according my tests. Could you provide us an example scene showing the issue to support@chaosgroup.com.

[nballiett]

Has there been an update to this? Or is there a workaround?

[hermit.crab]

After our developers' investigation, we determined that the light's visibility (even though invisible) in the fog is not a bug, but the way VRayLights function. Also, the light's exclusion from the fog is set through the VRayEnvironmentFog options (VRayEnvironmentFog nodes section, under Lights, untick Use all lights and pick out the affecting ones), rather than from the light's exclude/include settings. I presume this should suffice as a solution for your scenario.

[nballiett]

No, even when a light is set to invisible and I've unticked "Use all lights" in the VRayEnvironmentFog nodes section and have not included that specific light it's silhouette still shows up in both the alpha and rgb.

[hermit.crab]

nballiett Seems to work fine from what I tested (see screenshot, the left light is affecting the fog, the right is excluded). Could you attach a simple scene here so we can take a look? Also, what V-Ray and host platform versions are you using?

[nballiett]

I am using Vray Next 3.2 in 3dsmax 2018.

Sure thing. It does indeed work in your configuration.
However, I am using this to composite a character rendered separately from its background/environment. So while rendering the character I need to un-check "Affect Background" in the EnvironementFog options so I do not duplicate the fog while compositing and have a clean alpha for the character.

Here are some images attached to show what is happening, as was as a sample scene.

Do you think you could send me your scene from above as well?

My workaround as just been to use render selected for my character, but I didn't know if this is correct behavior. It seemed inconsistent.

[hermit.crab]

Thank you for the feedback. This is an already logged issue (internal bug-tracker id: VMAX-1326), however, its fix may take a while. A possible solution is to add a plane behind your character, though this would break the alpha and would require a second render.

The upper-mentioned scene is identical to yours, but here you go.

[nballiett]

Thanks! FYI the issue with cryptomatte and invisible lights that are not selected to affect the environment fog mentioned above is also still not functioning and leaving an outline in the cryptopasses.