specularity and energy conservation

[lacilaci]

Do higher specular values than default on glossy material break energy conservation? Do they on the new principled shader?

I'm asking cause I had some serious slowdowns with higher specularity on material, much more noise.

[Dade]

Do higher specular values than default on glossy material break energy conservation? Do they on the new principled shader?

No. Glossy2 material was written many years ago to replace Glossy material because the lack of energy conservation of the old version.

Do they on the new principled shader?

I don't know but I doubt Disney has designed a material without energy conservation in mind.

[B.Y.O.B.]

Just to clarify, what is displayed in Blender as "Glossy" material is named "Glossy2" behind the scenes in LuxCore.

Do they on the new principled shader?

From what I can see in the paper, only the clearcoat layer breaks energy conservation (a bit):

For our clearcoat layer, we use a fixed ior of 1.5, representative of polyurethane, and instead
allow artists to scale the overall strength of the layer using the clearcoat parameter. The normalized
parameter range corresponds to an overall scale of [0, 0.25]. This layer, even though it has a large
visual impact, represents a relatively small amount of energy so we don’t subtract any energy from the
base layer. When set to zero, the clearcoat layer is effectively disabled and incurs no cost.

(emphasis by me)
https://disney-animation.s3.amazonaws.c ... tes_v2.pdf

[lacilaci]

Thanks for clarification, so the one I'm using is glossy2 and it shouldn't break energy conservation.