LuxCoreRender Forums

Hi guys,
have you some suggestions to render mirror avoiding fireflies like the image below?

See the benches near the mirror on the left

marcatore wrote: Thu Jul 25, 2019 9:35 am have you some suggestions to render mirror avoiding fireflies like the image below?

You should try to make the light invisible in indirect light. LuxCore has an option for that (not sure if it is exposed on Blender). You can achieve the same effect using not intersectable light sources (like point lights, spot lights, etc.).

What type of light sources are you using ?

I'm using spot light for every light fixture.

About visibility for indirect I can't see any option available in BlendLuxCore.

marcatore wrote: Thu Jul 25, 2019 10:03 am I'm using spot light for every light fixture.

Mmmm, ok, so this is a different kind of problem. It should be this (i.e. the lack of MIS):



Can you post a scene with just walls, the nearest desk and a couple of spot lights covering the desk ? The fireflies over the desk top should be still there.

P.S. are you sure the source of the problem is the big mirror ?

Hi guys,
have you some suggestions to render mirror avoiding fireflies like the image below?

Try to work with small light and clamp value.

Light Value

Gain = 1
Efficay = 1
Power = 3 to 10

Clamp Value

Clamping = 5 to 50

Also make your emitting Object Simple: The part of your Spot with the emissive Shader on it should be very simple (Quad). And the large the quad less will be fireflies.

Try to not use glass or Arglass in front of your emitter (It doesn't make great visual diference and hit performance).

Dade wrote: Thu Jul 25, 2019 10:19 am P.S. are you sure the source of the problem is the big mirror ?

I'm not sure...but without them I don't have that fireflies.
I'm preparing a simpler scene and I'll send you.

Dade wrote: Thu Jul 25, 2019 9:46 am You should try to make the light invisible in indirect light. LuxCore has an option for that (not sure if it is exposed on Blender).

Yes, it can be found in the "visibility" panel. Note that this panel is only visible for light sources where it makes sense: sun and hemi (infinite) lights.
For point and spot lights it makes no sense because as Dade said they are not-intersectable anyway, and for area lights the panel is hidden because you are losing MIS if you disable the visibility (at least that's how it was until recently, not sure if that has changed?).

B.Y.O.B. wrote: Thu Jul 25, 2019 10:49 am are losing MIS if you disable the visibility (at least that's how it was until recently, not sure if that has changed?).

No, no, it is still true, the last change was about emitting light correctly for transparent meshes.

What engine and sampler do you use?