V-Ray 5.1: Animated Opacity on Blend Material Render bug?

[lars_gerstenmaier]

[seq]

Hi support and all V-Ray user,
using Maya 2022.1 (Win 10) with V-Ray 5.10.21 we today discovered that if we animate the opacity of the coat material and render the animation, the effect is not rendered. If we disable animation in the Render Settings, it renders correctly.

On the attached screenshot you see that we animate the Opacity from 0 (Frame 1) to 1 (Frame 2). If we render the animation the plane stays red.

Attached a the scene.

Best regards,
Lars

[seq]

Attached the scene.

forum Admin: If you can assign the first post to my account seq, it would be nice.

[seq]

My colleague fixed it with layeredTextures connected to the Blend Amount.

[hermit.crab]

Thank you for the report. There is a similar issue (most likely with the same source) with animated opacity in Layered Tex layers. The issue is logged (internal bug-tracker id: VMAYA-10537) and I've updated it with the VRayBlend case.

[seq]

Thanks Aleksandar.

[doppelgaengerdigital]

I had tough times the last 1.5 days figuring out that this is the reason for failure. When I have IPR running everything looks fine until I send to render an animation on the farm or even with batch rendering locally. The animation never gets rendered.
Has this ever been fixed? I am using Vray 6 with Maya 2023.3 on Win 11

[hermit.crab]

Not quite yet I'm afraid. The issue stems from the fact that the VRayBlend's opacity/blend cannot be animated (even though keyable). A workaround is to use a Color Constant for the Blend and animate it instead. Or animate the VRayMtl's opacity.

[doppelgaengerdigital]

Thanks! Yeah, the workaround works fine for now. Would be good to have it working without any workarounds.