Apple Motion 4 - Manual (Page 255)

Controls in the Media Tab of the Inspector
The following controls let you modify the objects in the Media tab, which also affects all
the instances of the object in the project.
Inspector Media tab
Separate layers in a Photoshop file do not use the following parameters. These parameters
are used only when a PSD file is imported as “Merged.”
Note: PDF files with transparent backgrounds do not have the Alpha Type or Invert Alpha
parameters.
255 Chapter 6 Creating and Managing Projects