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khan973
07-06-2014, 02:22 AM
Hi everyone,
I have a scene with hundred thousands trees and a moving camera.
I can't find the best AA setting for it.

Does somebody have experience for this and would whare some settings or tips?
my render is 1920x1080

Thanks

omichon
07-06-2014, 05:28 AM
Hey Khan,
Maybe posting your current camera settings and a screenshot of the camera view would be a good start, but In such situation I tend to increase Oversample quite a bit.

erikals
07-06-2014, 04:45 PM
wonder, does the Oversample kinda "blur" the AA effect ?

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edit: yes, seems so, somewhat... http://erikalstad.com/backup/misc.php_files/smile.gif

thanks to Tom Bosschaert "Exception"
http://www.except.nl/en/#.en.articles.94-lightwave-9x-anti-aliasing-guide


Oversampling:
This is an interesting one. It was added after many user requests to have the AA behave more like the old AA, which had this nice softish and forgiving quality to it. The new AA tended to be very harsh and needed much more samples to get nice smooth edges. In comes oversampling. In a way you can say that oversampling makes the sampling of AA extend beyond the boundary of the pixel it's supposed to sample by the amount of pixels set here. The old AA system had an oversampling of roughly equivalent from 0.25 to 0.5 hardwired, but now you can set this yourself. Setting a certain amount of oversampling will slightly soften the edges of your sampled pixels, which makes it more forgiving, making less samples necessary. Setting this too high causes blurring and artefacting. I usually stick to something between 0.05 and 0.2.

http://except.nl/lightwave/aa/Hand_AS_Overs.jpg

erikals
07-06-2014, 09:06 PM
Neat Video Noise Reducer is also a "must"...

it can be bought for a cheap price too, price examples >

Sony Movie Studio* = $50 *1080p
+ Neat Video Home* = $50 *720p

Sony Movie Studio = $50 *1080p
+ Neat Video Pro = $100

After Effects = $250 /year
+ Neat Video Pro = $100


* = software render size limitations

wellsichris
07-06-2014, 09:16 PM
not knowing your scene. best guess that I have used in the past
min 16
max 48
as .035
oversample .6
and neat video helps a lot. I have in the past render 2x bigger neat videoed it and then scaled it down. if you do that cut min and max in fourth.

hope that helps. I have in the past even had to go up to 96 to get clean forest renders. just depends on illumination.

wellsichris
07-07-2014, 07:46 AM
also make sure you are using clip maps not transparency on leaves.

Every4thPixel
07-07-2014, 08:27 AM
In most cases 1 for min samples is enough. If you can't get smooth results with a max of 32 samples than up the minimum samples. If you are using motion blur it's kinda pointless to use a higher value than one for the minimum samples.

I've got an alpha tip as well: Make sure your colorspace alpha setting is correct. Otherwise you'll get nasty edges.