noise on certain materials

[Nickh]

Hi,

I have an animation with a noise problem.

The scene is using GI, and is lit by 1 direct light with vray area shadows turned on. The only thing animated is the camera.

I calculated the solution every 10th frame using Irradiance map for the primary bounce (medium - animation preset, HSph sudivs 50, Interp samples 20), and QMC for secondary.

QMC sampler settings are noise threshold 0.002, min samples 16, global subdivs 4

Image sampler: Adaptive subdivision min -1 max 2 threshold 0.1

Antialiasing filter: Area

Some parts of the image are fine, but on others the result is that crawling noise effect, even on one material in particular which is a very basic vray material (just a diffuse colour - no bump or reflection)

Does anyone have any advice on which settings may improve things?

Thanks
Nick

[instinct]

for Final rendering -1/2 is definately to low. try 0/3 at least. Also i´d suggest using a different filter. If it´s for video i´d suggest Cubic.

Greetings,
Thorsten

[Clifton Santiago]

Are you sure you used "multi-frame incremental" when calculating the IR map? I've used even noisier setting than what you are describing, but the noise doesn't "dance" because its all "baked" into the one IR map.

[Nickh]

Thanks. I will try upping those antialiasing settings.

And yes, I definately used multi-frame incremental. If the noise still `dances` does this suggest that it is the antialiasing settings that are too low, rather than the irradiance map?

Cheers
Nick

[Nickh]

I still get it with adaptive subdivision set to min 1, max 4. and render times are too high with that anyway.

Does anyone have any other ideas?

Thanks
Nick

[Da_elf]

could be the amount of samples in your area shadow as well

[DanielBrew]

Hi Nick,

Have you tried increasing the 'blur GI' from the default of 0.

Dan

[Nickh]

If I turn area shadows off, I still get it. so I guess it must be purely down to antialiasing settings?

However if I use Adaptive QMC, I get a much better result. Still not perfect though, but i`ll have to go with it for now. I thought it would`ve been the other way round?

[Nickh]

Dan,

I used the preset for medium - animation, which is 8. what do you have this set to?

[DanielBrew]

I must admit I haven't changed it from the default as far as I can remember. I just remember when the blur gi thing was added Vlado's explanation was that it was to reduce gi flickering.

Dan