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View Full Version : Why is noise my vray animation ?


theistvanovics
07-28-2009, 07:24 PM
I made a Fly-through animation in a hadge maze. The camera walk around in the maze and flow up to bird perspective. The scene is fixed, the lights are fixed... just the camera is moveing.

The hadge and the grass are made with vray displasemant modifier. The render is made with vray GI LC. The First and the second too.

The render time is about 2 minutes / frame... it is very good for me comparing the irradince map very "low preset", who was 7 minutes / frame.

The problem is the animation is noise what i dont want, mostly the end of animation where the maze is showed from up.

My settings in vray 1.5:

Image sempler: Adaptive subdivision
Antialias: Area, Size 1,5
Adaptive subdivision sample: -1, 2
GI: Reflective: OFF
GI: Refractive OFF
GI Primary, secondary: Light cache

Light cache options:
Subdiv: 1000
sample size: 0.02
Scale screen
Nimber of passed: 4
Pre filter : off
Filter: Nearest, filter size: 10
Store direct: on
Adaptive tracing off
Mode: Fly-through

I work on a PC quad core 2.8, with 4 GB ram. 3D Max 9


Thank you for your help !

Best regards,
Istvanovics

theistvanovics
07-28-2009, 07:25 PM
The animation: http://www.istvanovics.hu/a/_teszt_labirintus_02.mov

jdollus
07-29-2009, 03:52 PM
you need to precompute your gi (not just light cache) and up the image sampling. Your adaptive subdivisions should be positive value and ,generally speaking, no more than two values apart for stable animation so use 1 and 3 instead of -1 and 2.
also, with displacement, you should add some minor blur to the vraydisplacement modifier to reduce flicker.

MikeBracken
07-30-2009, 01:39 AM
As John said, never use any negative numbers in the sampling. In my experience small details can be missed completely. I always use 0 at least for the minimum. And with very fine displacement you will almost always expect some noise. There just seems to be to many faces occupying a pixel that it is hard for any renderer to clean it up (although this problem is "almost" non existent in Renderman). This is the main reason that we dont render geometry/displacement grass in animation here. I have tried rendering the grass seperately at double the resolution, and it still was not enough.

That said, as fast as the camera is moving you could probably soften it a bit with slightly heavier motion blur in post.

Regards,
Mike

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