Light Cache pass - black VFB

[pavol_pastork]

Hi,
I cannot find similar issue in forum, so I write here.

Whenever I open project, the first bucket renderis fine, but every other render in same project start with black light cache pass. Sometimes it reveals by turning off Lens Effect Layer in VFB. Or when Lens effects are off, then turning it on reveals light cache pass, but after few seconds it turns black.
I work in Rhino 7 and V-ray 5, latest.

Thanks
Pavol

[nikoleta.garkova]

Hi pavol_pastork

Would it be possible to share more info on the project's Render Settings, or ideally get in touch with us through our contact form and share the project with us so we can investigate further? Make sure to use the Pack Project tool from Extensions > V-Ray > Pack Project and please mention this thread in the email, thanks.

[pavol_pastork]

I send project through contact form. It turns black after 1st final rendering. Every other rendering has black light cache pass. The problem is at my few latest projects.

[javierrentas]

Any solution for this issue? I have the same problem when rendering in GPU

[nikoleta.garkova]

Hi guys,

I've managed to reproduce this, it appears to be happening when Lens Effects is enabled and LightMix RE is added. LC pre-pass will show prior the first rendering, and upon any subsequent rendering LC calculation will follow with a black VFB screen. The image seems to start rendering just fine afterwards. If any of the two is disabled (Lens Effects or LightMix), however, the issue won't occur.

javierrentas, please confirm if that's the case in your situation as well. This is also apparent on Progressive rendering.

I've logged this in our internal bug-tracking system under ID number: WEBUI-5735 for developers investigation. Will let you know when there are any updates on the matter. Thanks!

[javierrentas]

Hi Nikoleta
Thank you! Yes, that is exactly the issue. Thank you for taking the time and looked at this.

[pavol_pastork]

Thank you Nikoleta for info.

[konstantin_chaos]

Hi guys,

V-Ray 5 for Rhino, update 1 was recently released.
A number of fixes and improvements were done to the VFB.
I also appears that the specific issue described here is also resolved.

Can you give it a try and let us know?

Konstantin

[pavol_pastork]

konstantin_chaos Tried few renders without any issues.

[konstantin_chaos]

OK, great.
If the issue resurfaces in any specific situation, please let us know.

Konstantin