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visualasylum

06-05-2003, 07:39 PM

I'm rendering an animation sequence where I will be cueing the background to put it an animated Sky.

My question is, in the Rendering preferences, there's a function to "Don't Anti-aliased against background", and I'm not sure wich one to pick, since if I don't select anti-aliased function, I'm going to get jagged edges, in the end, and if I select to antialiased to background, when cueing the background out, I will get strange coloration at the edges, since it tend to render the background color in max at the antialiased edges.
http://www.visualasylum.net/incoming/max_rendering.jpg
Can someone give me soe proffesional advice here?

thanks in advance.

G

Marcel

06-05-2003, 08:10 PM

I can't see your image :eek:

You should definetely use antialiassing against the background. The trick of rendering in passes is to render against a black background and using correct settings in the compositing program.
In After Effects for example you have to let the program know what color you have used for the background when importing. If all goes well you shouldn't see any coloration of the edges at all.

EricChadwick

06-05-2003, 10:24 PM

Either do that, or turn off pre-multiply alpha. The RGB will look jagged, but the alpha will be AAd properly. In fact, the RGB will bleed out a little so none of the bkg colors are grabbed by the alpha... just the RGB.

More info in the help file. Search tab is your freind.

Also here's some sample images...
http://www.micro-intel.com/users/ypoissant/tutorials/Alpha-about.htm

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