VFB, using Background Element and Denoiser

[JonasNöll]

Hi,

there seems to be a problem when using the background element in VFB in combination with Denoiser:

- It only occurs with NVidia or Intel Open Image Denoiser, the Default V-Ray Denoiser seems fine
- It only occurs when Background Element "As Foreground" is disabled.
- What happens: Background shows correct until denoiser kicks in. Then the colors are shifting and there is lots of color bending.
- Strangely it doesn't appear if hiding the Denoiser Element, it seems baked into the background element somehow, but the problem only occurs when having Denoiser enabled so it must have something to do with it.
- Effect is most visible with dark background images

[Alex_M]

I can confirm. Same issue here.

[boyan]

Hey,

Thank you for the reports, I think I found what's causing that issue and if possible to disable the Dome light option's -> Spherical (full dome) light when you're using Nvidia or Intel denoiser this effect will disappear on VFB. This is not a workaround just an option if needed.

Cheers,

[Alex_M]

Thanks for the tip, boyan !

[yavor.rubenov]

Hello,

Can you check the alpha channel and its values - there were cases that caused the AI denoisers to mess alpha and to make it 2.0 or values less than 1.0. Then the background correction reads that alpha values and uses them for blending.

Best regards,
Yavor