Alpha channels?!

[thesamenio]

Hello!
I'm new to AE, as a matter of fact i got it just for one reason. And this reason is my problem. So the question is.
For instance i have a clip with a palm tree in a wind. How would i take everything out, except for the palm tree. So in the video clip all you would have is a black background and a palm tree. I want to export it in flash afterwards. So i heard something about alpha channels, but dont know lots . SO i hope that i made my question clear!

 

[maruyama]

You can do it two different ways.

The first way is to KEY the surrounding material out. Similar to Photoshop's magic wand tool, there are several KEYING tools in After Effects that will help you select and remove ranges of pixels.

The second way requires you to draw a mask shape around the palm tree on each frame, animating the mask throughout the clip. It's very tedious work, but sometimes the only way.

HTH

Ko

Ko Maruyama
Free Tutorials

http://homepage.mac.com/komaruyama/Tutorials