Apple Motion 4 - Manual (Page 333)

Suggested uses: The Screen blend mode is especially useful for knocking out the blacks
behind a foreground subject, instead of using a Luma Key. It’s mainly useful when you
want the rest of the foreground subject to be mixed with the background image as well,
based on its brightness. It’s good for glow and lighting effects and for simulating
reflections. You can also use the Add, Lighten, and Color Dodge blend modes to create
variations of this effect.
Top object Bottom object Screen composite
Color Dodge
Whites in either the foreground or background image are preserved in the final image.
Blacks in the background image replace the foreground image, while blacks in the
foreground image become transparent.
Midrange color values in the background image allow midrange color values in the
foreground image to show through. Darker values in the background image allow more
of the foreground image to show through. All overlapping midrange color values are
mixed together, resulting in interesting color mixes.
Reversing the two overlapping images results in subtle differences in how the overlapping
midrange color values are mixed together.
Boxes object on top Monkey object on top
Linear Dodge
Similar to Screen, except that lighter midrange color values in overlapping regions become
intensified. Blacks in either image allow the overlapping image to show through
completely. Whites from both images show through in the resulting image.
333 Chapter 7 Basic Compositing