Blotchy Walls in Interior Scene

jordantheperson · November 15, 2018, 05:56:33 AM

Trying to figure out what causes these blotchy walls. Settings are the default interior settings, so Shadow Quality = 2, Ray Bounces = 16, Global Illumination Bounces = 10.

The Keyshot manual does not explain much and I don't want to wait 2 hours to see if any changes helped. The material on the walls is the diffuse wall material. The floor is a procedural material I created to replicate polished concrete.

The render was set to run for 2 hours which I think came out to 405 samples.

All lighting is environmental using two pins.

mattjgerard · November 15, 2018, 06:40:53 AM

No real solution, as I know very little about interior rendering. There are people on here that are great at it so they will probably chime in.

But for the speed thing, use the render region tool to isolate a small section of the wall, it will "sample up" a ton faster and allow you to make adjustments and troubleshoot so much faster. The render region is critical to my work with cloudy plastics and spotlights shining through them. They take a while to settle down, so it really helps.

jordantheperson · November 15, 2018, 06:55:47 AM

Ah right, I am using the region render now to test higher ray bounces and GI bounces. Not seeing improvement though.

jordantheperson · November 15, 2018, 09:13:58 AM

Its starting to even out at 7000 samples.... Maybe I am asking too much of the environmental lighting.

RRIS · November 19, 2018, 06:28:12 AM

Do you need 10 GI bounces? I hardly ever go over 4..

sleby · November 21, 2018, 06:19:16 AM

I too noticed that quite often when using wall material.
Now I just put diffuse white and adjust if needed onto the walls and it also renders way quicker.
Post if you find a solution though.

bdesign · November 21, 2018, 06:46:05 AM

The blotchy pattern looks the same as the texture on the floor material (it looks like this same material may be applied to the ceiling?). If the walls are a Diffuse material there would be no reflectivity, so perhaps it is a bounce light pattern from the floor/ceiling? Does it improve if you turn off the texture on the floor/ceiling material? Have you applied any bump map to the walls?

Cheers,
Eric

jordantheperson · November 27, 2018, 06:10:13 AM

Quote from: RRIS on November 19, 2018, 06:28:12 AM
Do you need 10 GI bounces? I hardly ever go over 4..

That is the default for the interior lighting setting. I am guessing this is needed. Changing the GI bounces also changes how bright the scene is (at least using interior lighting). Areas get blown out that shouldn't be blown out, etc.