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View Full Version : Masking an object for compositing - render layers??


Rick Davidson
12-12-2006, 12:28 AM
Hi guys - er see this picture right? :) It's a halo that I'd like to mask the centre of and create an alpha file for compositing - see the inner disk? I've tried rendering that object as a geometry matte in render layers but it renders the entire disc - I want the halo itself to obscure the mask in front of course. Help?

http://www.rickdavidson.com/extra/mask.jpg

acidream
12-12-2006, 05:31 PM
You should put a black hole shader on the parts you want to chop out of the matte. Create a Shading Map, and set the Matte Opacity to Black Hole and apply.:)

wabash
12-12-2006, 06:39 PM
You can also use the use background shader and set all of it's attributes to 0, and assign that shader to the faces you don't want included in the alpha.

Rick Davidson
12-12-2006, 07:47 PM
wow thanks guys, I'll try that

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12-12-2006, 07:47 PM
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