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View Full Version : DOF Noise - how to eliminate?



Getting Board
02-20-2011, 03:16 AM
This is my first attempt at using DoF and it's immediately frustrating.
I've used several camera and lens variations, oversampling and now motion blur in an attempt to remove DoF noise.

I've read some posts here about issues with DoF noise, but I haven't found a good solution yet.

Surely there's absolutely no way that a company creating 3D software, which has a DoF option built-in, would ship it KNOWING that there are major issues with noise when this feature is used.

What do I need to do to remove this horrible noise?

You can see the settings I used for the image I attached. There's been almost no improvement over what you see, regardless of the changes. The image has come out different, but not better and certainly not useable.

This boggles my mind. It seems broken. Surely I'm missing something in the settings...... right?

bazsa73
02-20-2011, 03:25 AM
Fix it in post.

OnlineRender
02-20-2011, 03:28 AM
Render Setting ? I gather reduce noise is selected .

archijam
02-20-2011, 03:46 AM
Turn up AA, but this will slow down your rendertimes.

This is why many renderers still do DOF in post with plugins, or a depth pass .. it's just faster to compute.

edit:

http://newtek.com/forums/showthread.php?t=96199

(tho note toby overules my setting advice ;) )

and of course:

http://www.except.nl/lightwave/aa/index.htm

Iain
02-20-2011, 07:38 AM
Try raising the F-stop value a little. Are you using a Null to control the focus?

I've always found fprime's DOF prettier than LW's but a lot of people like this exaggerated effect. If there is a light source in the background it can look amazing.

Getting Board
02-20-2011, 08:18 AM
Thanks, guys.

I'll try your suggestions and let you know how it turns out.

You guys make this forum a priceless resource.

Thanks again

wrench
02-20-2011, 08:26 AM
The other thing to do is up the number of Motion Blur passes, non-intuitively enough. Motion blur and Photoreal DoF are linked. If your scene uses subpatched objects it will mean the renderer needs to calculate their breakdown again (just like the good ol' days).

B

funk
02-20-2011, 01:32 PM
Enable adaptive sampling and set the threshold to 0.03 or lower.

Amurrell
02-20-2011, 07:44 PM
This is one of the reasons I prefer digital confusion, but it doesn't work with perspective camera (as it creates "transparent objects" when they shouldn't be), but does apply the effect after the render is complete (AA and all), unlike the classic camera which does work with it, but calculates DC every pass of AA, blowing up render times.

Hieron
02-21-2011, 10:09 AM
Boggles the mind? :) geez

-Do it in post. Better 90% of the time and many many times faster. Not when using transparant materials though.
-If you must, use insane AA in LW, 8 AA won't cut it.
-If done in LW and with animation, remove noise with NeatVideo

Some Neatvideo tips:
-Do NOT use AS since it will mess up the supernice 1 pixel 1 frame, noise frequency NeatVideo will pick up and fix. (AS is nothing special in most shots anyway)
-Do not use reduce noise in rendersettings. same as above.