ADOBE AFTER EFFECTS: Forum Expressions Tutorials Creative Cloud

How to change a black background into transparency?

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Andre LuisHow to change a black background into transparency?
by on Aug 27, 2011 at 3:08:20 pm

Hi pals!

The f*cking client sent me their animated logo in a .mov with a black background on it. Today is saturday and they won't be able to send me the thing with proper alpha channel.

I can't figure out how to change its black background into transparency, don't work with any blending mode nor matte options, etc.

Is there a way to fix this?

Thanks for your time and your help!



Return to posts index

Dave LaRondeRe: How to change a black background into transparency?
by on Aug 27, 2011 at 3:40:17 pm

You'll have to build a matte to create the transparency. I would google "Knoll Unmult". It's a free plugin, and it creates transparency based on luminance. It can help a lot. I would also experiment with the Shift Channels effect, or one of the many other effects under the Channels category. Used in combination, they can help a lot to create mattes.

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA


Return to posts index

Andre LuisRe: How to change a black background into transparency?
by on Aug 27, 2011 at 11:16:43 pm

Thanks Dave. In the end, I still lose some of the black in the logo, but the unmult effect still is better than shift channels, or some other solution. I'll send 'em this version and if they complain about, I'll ask for a proper video with alpha. Thanks!



Return to posts index


Victor NguyenRe: How to change a black background into transparency?
by on Aug 27, 2011 at 5:29:22 pm

Well you can still do the good old rotoscoping to rotoscope the logo animation


Return to posts index

Darby EdelenRe: How to change a black background into transparency?
by on Aug 28, 2011 at 1:50:29 am

The Keying > Extract effect allows you to key an image using luminance (or a color channel). You can soften the transition from full alpha to no alpha. You can then also apply a Channel > Remove Color Matting effect set to Black to remove the black spill you'll have in the alpha.

Darby Edelen


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]