Pixel bleeding at edges

Hi guys,

I’ve been working on an arch-viz interior, and I’m trying to get the lighting on all the walls as clean as possible.
I’m able to get really far with the awesome information from the lightmass topic and Rafael’s workflow guide, but I just have this last problem that I’m trying to fix.

At some of the intersection of the walls I get these black pixels bleeding which stand out quite a lot on white walls.
I understand that I would be able to get rid of this if I would attach all walls together into one mesh, but this would be a lot of work and I would have to use a ridiculously high lightmap size in order to cover these walls and ceilings.

So what I’m asking is; is there another option that I’m missing that I could use to get rid of this problem?

Settings that I’m using in this scene:

Lightmap size on walls and ceilings: 512 to 1024 depending on their size. (I think this should be enough since it’s orange colored)
Ambient Occlussion: Off
Static Lighting Level Scale: 0.25
Number of Bounces: 100
Indirect Lighting Quality: 10
Indirect Lighting Smoothness: 1

NumHemisphereSamples: 512
NumIrradianceCalculationPhotons: 2048
IndirectPhotonDensity: 6000
IndirectIrradiancePhotonDensity: 4000

Thanks in advance :slight_smile:

Remove Ambient Occlusion or reduce it to very low value. If you want to have large Ambient Occlusion, then play around with the Radius value which will get rid of this bleeding.

Sandermer already said/wrote that AO is off. I also had similar problem, and I solved it by scaling back the Static Lighting Level Scale to its default value ‘1’ (previously I was using 0.25 as well).

I’m not an expert in this but as tupikp said, raising the scale value helps. If you look at rafael’s article, the first images he posted was to show what this value does. It adds more definition to the shadows at the expense of introducing shadowing bugs that can be solved by jacking up photons, etc.

There is also a hack to solve this and that is to make the areas you know will be black into their seperate UV islands so they can bleed black pixels all they want without messing your white walls.

Thanks guys, I do really want to keep using a lower Static Lighting Level value though, as it really increases the quality. I will try the technique that cora mentioned :wink: