Light leaking in Vray for Sketchup

[kelvintaylor]

Hello there,

 

I've been having issues with vray lights leaking on the other side of surfaces. I've tried to add an additional interior structure to stop any light from transmitting through as well but it doesn't seem to help. The lights are also not double sided so they shouldn't be illuminating behind them (I think).

 

If you look on the top of the light surrounding the steps you can see it leaking quite noticeably.

 

I added a inner surface to try to fix this. It didn't work however.

[Francisco Penaloza]

This also depend of what type of Gi are you using.

Any ways I would model that area as a C shape with thickness, then place inside a rectangle light or a cylindrical or whatever fit there.

Not sure if you can use shapes as light on V Ray for sketchup. but a rectangle light should do fine.

Do not use the same geometry as light source.

[SkylineArch]

is the "light" a material with emissive layer in it or an actual Vray light?

 

If you're not using one in this image, use a Vray Physical Camera, it should help.

 

If you are, make sure the geometry is "air tight", and perhaps try a higher quality render preset

[kelvintaylor]

That's actually a square vray light, I wasn't very specific in my post about that. I tried to encapsulate it in a second layer too just to see if that would block the light. Didn't work though. :/

[kelvintaylor]

The light is an actual Vray light I also use the physical camera in Sketchup. I made sure it was air tight, even adding a thickness just to make sure. Its hard to tell in the screenshot but that's what I tried to show. It's really making me scratch my head.

[SkylineArch]

hummm, not sure either. Maybe just up the light's subdivs or see if it's double sided

[Francisco Penaloza]

Not sure if I read correctly your screen shot. To explain my comment, please referrer the image bellow.

It would be better if you use the option B instead the option A.

even tho you have a geometry with some thickness, if this surface is not thicker than the radius of interpolation for Light cache, the sample will cross that surface, creating the light leak.

One easy way to check if it is your geometry or not, is render brute force, if there is not light leak then you know you need to refine your light cache and Irradiance. smaller samples, but you'll need to increase the amount of them to compensate.

Also you could try to un-check retrace on Light cache