X-post from Odforce

https://forums.odforce.net/topic/44865-light-sampling-issue-mantra/ [forums.odforce.net]

Quick question.

This is the diffuse AOV from a render using nothing but a distant light.

To give you an idea, this scene is rather large. The geometry in this scene is a ocean volume and a plane. I have removed the displacement map from the material to isolate this as much as possible. I can not for the life of me find what sampling quality I'm missing here.

Does anyone recognize this kind of circle pattern coming from the light?

SOLVED: It's not a light, its not a sample. ITS FOAM.

When writing out the spectra and you're not using the foam, turn it off.

Turns out those circles are gigantic, I mean impossible to recognize as such foam particles.