View Full Version : Anti Aliasing Problems

05-18-2005, 07:24 AM
Hi guys,

Im having some AA problems. Thats very weird because I never have.
I rendered an animation at PLD-3 with Mitchell and it looked horrendous.
I am now rendering stills with Enh. Low and Classic or Mitchell reconstruction and its still pretty bad.
At first I thought it might be very bright areas which are rendered wrong, but thats not the case.
Look at the below render. It has Enh. Low with Mitchell reconstruction, and no Adaptive sampling.
There's a slight motion blur of 50% and the cam is moving very slowly.
This is not right, is it?

Whats goin on?
Look at the white facade of the building in the righthand side of the image, and the parking lines...

This is with an otherwise fresh lw 8.3...

05-18-2005, 07:55 AM
This is typical of the results I've been getting, on scenes like this with a lot of thin straight diagonals in the rendered image. In a test when the PLD AA's first came out, the PLD method provided no speed increase for similar quality. In fact classic low looked better than PLD 1-4. PLD 5 started to look better, but actually took longer than classic low. (I did the test with the classic Reconstruction Filter.). Hate to say it but you may have to take the time to boost the AA up a lot higher for this type of scene.

How does it look at the next level-- classic medium or PLD 7 or 9?

05-18-2005, 08:24 AM
I have yet to test, but that makes the render times unacceptable...

05-18-2005, 01:04 PM
Some tests...

Classic low seems to be the best still, but its all rather unsatisfactory.
Does anyone have any hints, like, what would adaptive sampling help in this case?

worst of all seems to be Guassian: blurry and not AA-d at all. Mitchell still seems to perform best with PLD, but when using classic filter with PLD, you can save up to 25% rendertime. Nuts!

The differences can be best seen when saving the images to your disc and fliccing through them with an image viewer.

05-18-2005, 01:12 PM
Here the various 5 pass options.
Notice the full minute increase of rendertime when choosing mitchell over classic reconstruction when using classic low AA. Very odd.

05-18-2005, 01:39 PM
Sorry for the bandwidth people, but this might actually help someone choose : )

2x blowups.

05-18-2005, 05:49 PM
Just 2cents from me:

box is blurry, but a good friend for the "half to one pixel size" details: Has one of the best "pixel step blending" when it comes to the close to vertical or horizontal details.

Lancos at low AAvalues: The same reults, like using a classic filter and run a sharpening filter in post, at very high AA values results resemble classic medium.

PLD and Mitchel. Good Friends for less detailed scenes and for low AA settings. Got some problems with a DOF scene. Close to horizontal lines with sharp contrasts start to flicker(in AA) and get very edgy.

I'm just staring to gather real experience in the usage of PLD<->Classic Classic<->Mitchel, and your info is a good help.