ABSTRACT
A matte can be a grayscale still image, another movie, or an animated graphic such as text. At the end of the day, After Effects sees it as a collection of grayscale levels which it uses to define the transparency of another layer. Understanding matte logic and how to use mattes in a hierarchy of comps is one of the keys to creating complex animations. One of the most powerful features of After Effects is its ability to create a hierarchy of nested compositions. Nesting is useful for project management and ease of editing, but it is also necessary to achieve specific effects. Nesting is by far the easiest way to set up a track matte hierarchy. Matte layers with luminance values that change over time can make for interesting fades in an underlying movie file.
