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JaMo
04-25-2006, 04:15 PM
im using .rla's in AE 5.5

is it possible to use alpha as a mask for applying effects?

i want to seperate certain elements without re-rendering everything. is it possible to render out only the alpha and use that for a mask for applying effects and layer transitions(overlay,screen,multiply)

basically i want to seperate her sword, body, and wings. ive tried rendering out the alpha for the body and then the alpha for the sword and composite them together but i cant get the sword alpha to subtract the body alpha. for example if i apply a blur to the body the tip of the sword that intersects the body also gets blurred. is there any way to do this without rerendering the scene?(rendering out the alpha would be ok)

here is the render

http://www.geocities.com/feedback3d/angel_example.jpg
Mylenium
04-25-2006, 07:55 PM
im using .rla's in AE 5.5

is it possible to use alpha as a mask for applying effects?

i want to seperate certain elements without re-rendering everything. is it possible to render out only the alpha and use that for a mask for applying effects and layer transitions(overlay,screen,multiply)

basically i want to seperate her sword, body, and wings. ive tried rendering out the alpha for the body and then the alpha for the sword and composite them together but i cant get the sword alpha to subtract the body alpha. for example if i apply a blur to the body the tip of the sword that intersects the body also gets blurred. is there any way to do this without rerendering the scene?(rendering out the alpha would be ok)

here is the render

http://www.geocities.com/feedback3d/angel_example.jpg

I don't really understand what your problem is. Look up what AE's matte modes are for and therein lies your solution. Basically you have to use your swords alpha to make an unblurred duplicate of your layer appear where it should and then vice verca clip out all blurred areas from the sword.

To answer your question: No, unless an effect provides an explicit dropdown to choose specific channels or layers to drive its internal parameters, AE will only treat them for what they are - simple Alpha and color, respectively. No more, no less.

Mylenium
JaMo
04-25-2006, 08:07 PM
ok ill look into matte mode. i dont know much about compositing but basically im trying to make the alpha act like a mask. for example in photoshop i can use tools like the lasso to marque what i want affected by filters.


ill try what you said.
JaMo
04-26-2006, 12:14 AM
ok ive messed around with matting and got it to work....sort of. the one layer mode i want to use (stencil lumina) is not behaving. its its blowing out the other mask. ill put up a render in a few minutes to show what i mean.
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04-26-2006, 12:14 AM
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