Crawling Noise in Animation

[Infrared digital]

I am experiencing major crawling noise in one particular animation. Its almost as if (if you can imagine in Photoshop) the top layer has a noise filter applied to it then a screen blending mode added. So, it sits over the entire frame not moving but it creates this crawling noise effect when the animation moves.

Because there are moving objects I am using the Irradiance Map Pre render and Animation settings with LC. The settings are quite high and I would most certainly not expect to have noise in any other scene.

[vlado]

Can you show a few frames or crops of them?

Best regards,
Vlado

[Dariusz Makowski (Dadal)]

Brake it apart and see which render pass cause issues...

[Infrared digital]

Here's a very short clip which shows the problem;

http://dl.dropbox.com/u/7925881/NOISETEST.mp4

You can see it most if you look at the bottom half of the recess.

Incidentially, this is a low res test using Cubic anti-aliasing - which didin't help.

[LarsSonparsson]

It looks like you have "Time independent" checked in DMC Sampler settings.
It usually creates that kind of effect.

[Infrared digital]

I think you might be right Lasse, I am doing a full res render and will let you know.

[Infrared digital]

Yeah, that has sorted it but, the render times have gone from 10 minutes to 1.5 hours per frame - is there a way to reduce this ?

The pre calcs times are normal but it is the render times that are massively increased.

Thanks

N

[LarsSonparsson]

Hmm... that's weird. I haven't noticed that "time independent" has any effect to render times.

[vlado]

Lasse is right, the "time independent" option doesn't have much effect on render times unless something else is going on.

Best regards,
Vlado

[Infrared digital]

Thanks for your help, it sorted the noise but, the render times doubled so there must be something else going on - I am not sure what.