GI Problem

[amberspice]

Hey guys,
I am having problems getting a clean GI on my interior rendering (ceiling area).
Even though i tried different settings, I can’t get rid of the splotches…
I use Irradiance map and Light cache for GI, resolution of my rendering is 1240x1754 px.
Has anyone got a solution for that problem?
Thank you very much.
Tobi

[tashko.zashev]

Hi,

The light leaks in this render could be due to the light cache settings.
You can make a test without secondary GI engine.
If that fixed it, try to turn on LC and increase the subdivisions.

[amberspice]

Hi,
Thanks for your support.
I made some tests without secondary GI engine, but the splotches remain.
But the lower the Irradiance map settings, the smoother the result.
Brute force and Light cache also works fine.
Again, thank you for your help.

Tobi

[Morbid_Angel]

try setting high interpolation sample for your irmap, for example 150/150…

[tashko.zashev]

Also as addition, you can turn on " Check sample visibility" in IRR parameters and increase the “Secondary ray bias” value to 0,001.
If you still get any issues with this scene, you can send it to vray@chaosgroup.com, and we will look into it.

[amberspice]

Hi,
I finally got some time to do a test…
Seems like increasing the interpolation samples solved the problem.
I also turned on “Check sample visibility” and put the “Secondary ray bias” value up to 0,001.
Thank you very much for your help, I really appreciate.

[Morbid_Angel]

If I remember correctly, the more interpolation sample you have the smoother the gi solution will be, thus less precise, and if you are looking for accurate shadows that might be blurred too much, so you would have to oversample your prepass. But since you are using detail enhanced brute force sampling for close proximity object this shouldn’t be a problem so that’s why it works