Apple Final Cut Pro 5 - Manual (Page 1165)

378 Part II Project Interchange
Displaying backgrounds
When working with clips that have an alpha channel, you can choose different
backgrounds to make it easier to see which areas of your picture are transparent. There
are four backgrounds to choose from:
 Black
 White
 Checkerboard 1
 Checkerboard 2
Note: You can also choose View > Background, and then choose Red, Green, or Blue
from the submenu to use one of these solid colors as the background.
Superimposing Video When Preparing for EDL Export
In an Edit Decision List (EDL), a Super or Key track is the equivalent of a single
superimposed video track in Final Cut Pro. EDLs can recognize only one Key track, so
V2 is the only video track other than V1 that appears in an exported EDL. Transitions
in V2 are not allowed in EDLs and are ignored. If you want to use a transition in V2,
use keyframes in the opacity overlay to dissolve V2 up and down. (See Volume IV,
Chapter 10, “Importing and Exporting EDLs.”)
The opacity overlay in the Timeline appears as the “Key Level” in your exported EDL.
Opacity keyframes, if they exist, are translated into values for the Key Level and are
calculated in the EDL in relation to the timecode of the master tape. These numbers
are for use by a video switcher. Some online systems can translate these for
automatic use by some switchers, but more commonly they are used only as notes
for the editor to use in an online session. These values and their locations appear as
notes in the EDL.
Translucent clips or generated text
may be more visible if you choose a
background that emphasizes them,
such as Checkerboard 1 or 2.