Settings and – Apple Final Cut Express HD User Manual
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Settings and Options in the RT Pop-Up Menu and Playback Control Tab
The following section describes the settings and options in both the RT pop-up menu
and the Playback Control tab of the System Settings window.
Playback Settings
 RT pop-up menu:
 Safe RT: Selecting this option guarantees that effects are played back at the quality
and frame rate specified for Playback Video Quality and Frame Rate, and that no
frames are dropped during playback. If Final Cut Express HD anticipates that your
computer won’t be able to perform all the effects calculations in real time, the
render status of that portion of the Timeline becomes red, which means you have
to render before you can play back. If you enable external video monitoring, this
adds additional load to your computer’s processor and the Safe RT option takes
this into account. This means that fewer effects will be processed in real time.
Note: Even though the Safe RT option guarantees no frames will be dropped due to
CPU limitations, frames may still be dropped if your scratch disk cannot maintain the
necessary data rate during playback. This can be a problem if you have multiple video
streams playing from a relatively slow hard disk. In this case, the Timeline may show a
green render bar, indicating that the CPU can handle the effects load, but you may still
drop frames due to slow disk performance. To solve this issue, you can limit the
acceptable real-time data rate of media playback in the General tab of User Preferences.
For more information, see “
Choosing Settings and Preferences
 Unlimited RT: Selecting this option tells Final Cut Express HD to play as many
frames as possible when your effects exceed the processing power of your
computer. Final Cut Express HD does this by spending time to process some
frames in real time while skipping others completely. Unrestricted real-time
playback allows you to play more effects, but increases the likelihood that your
sequence will drop frames during playback.