2 Replies Latest reply: May 21, 2012 1:36 AM by Karel Bata RSS

    combining the alpha channels?

    Karel Bata Community Member

      I'm missing something really obvious here, but what is it?


       


      I want to have a subject casting shadows on a moving clouds background. Here's the clip so far using a method that doesn't works quite well enough :


       



       


      The shadow doesn't work on the darker parts of the cloud. That's not really so much of a prob in 2D, but this is a stereo 3D project and having the shadow intermittently disappear looks odd.


       


      So, to create a shadow that I can then insert between the two Images, I need to combine the alpha channels from the two videos (one created using green as a key, the other the blue sky).


       


      How do I do that? I bet it's really obvious!


       


      Cheers! !http://forums.adobe.com/images/emoticons/wink.gif|___jive_emoticon_name=wink|jivemacro=emoticon|class=jive_macro jive_emote|src=http://forums.adobe.com/images/emoticons/wink.gif!


       


       


      Currently using CS5