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Steamthrower
08-06-2007, 09:57 PM
Classic, Box, Mitchell, Gaussian, and Lanczos...can someone elaborate on these different AA filters? I know some seem to render better/faster than others for me at different times, but what's the root behind them? Are some more appropriate for different applications than others?

At the moment I go with whatever I like the best. Is there a concrete guideline that I need to follow?

loki74
08-07-2007, 12:05 AM
I don't really know anything about the reconstruction filter, but usually when I see the terms "box" and "gaussian" used in the same context, I think of weighting kernels. If I were to hazard a guess (and assuming my understanding of the LW renderer is somewhat accurate), I would say that it has something to do with how the result of each raytrace is converted into pixel data. I always use classic.

For AA, I would highly advise against PLD. "Classic" seems to imply something old and less powerful, but I find that I always get better results in less time using Classic. Although, sometimes it is nice to have an arbitrary pass render, and Classic is locked into set intervals...

jameswillmott
08-07-2007, 12:35 AM
Loki is right, they refer to weighting kernals.

Classic is almost the same as Box. Gaussian is quite fuzzy but good for heavy motion blurred/DOF scenes. Lanczos sharpens edges a lot, Mitchell sharpens edges just a little.

toby
08-08-2007, 04:02 PM
For AA, I would highly advise against PLD. "Classic" seems to imply something old and less powerful, but I find that I always get better results in less time using Classic.
AB-solutely. PLD is garbage. You have to set it higher than classic to get equal quality, and that takes twice as long. It's also incapable of AA-ing fine lines.

Can't say I like Gaussian at all either, and not just in LW, I've tried it in Mental Ray and it's the same; if your anti-aliasing is not high enough, you'll have blurry pixels - ugly and cheap-looking. If it is high enough, then you're blurring a perfectly good image. Blur it in post, not in the render!

Steamthrower
08-08-2007, 04:04 PM
OK, thanks all.

PLD is garbage. Got it.

Glendalough
08-08-2007, 05:49 PM
OK, thanks all.

PLD is garbage. Got it.

This is true.

It should be dumped, the camera panel is complicated enough without it.

Lanczos buzzes badly in animations, but is great for really stark images.