Apple Final Cut Pro 5 - Manual (Page 1152)

Chapter 18 Compositing and Layering 365
II
 Overlay: Wherever the color value is more than 128, Screen is applied. Wherever the
color value is less than 128, Multiply is applied. In this example, the layered image is
rendered semitransparent, with its opacity in different parts of the frame varying
based on the brightness of the foreground and background images.
 Hard Light: Darkens or lightens the colors of the selected clip, depending on the
color values for that clip. The effect is similar to shining a hard spotlight on the clip.
In this example, the lighter parts of the layered image of the swirl become the
most transparent, brightening the parts of the background image of the drums
that show through.
 Soft Light: Darkens or lightens the colors of the selected clip, depending on the color
values for that clip. The effect is similar to shining a diffused spotlight on the clip. In
this example, the lighter areas of the layered image of circles lighten the background
image of dancers, while the darker areas darken it.