Monitoring Your Work
The largest single element in the iMovie window is the Monitor (see Figure 3.2). You use this window to play and edit your video clips. You also use it to view the entire movie as you assemble it. The Monitor window contains the controls you use to edit and play your clips.
The playback and volume controls work just as you probably suspect they do. You can use the playback controls to rewind/review, fast forward, play, or stop your movie. You can adjust the volume using the volume slider (drag it to the right to increase the volume, and drag it to the left to lower the volume).
The Home button always moves you to the beginning of your movie.
The Play Full Screen button causes the video to be played back using the full screen (the Monitor consumes the entire window). The Full-screen mode helps you focus on your video; you aren't distracted by the other elements of the iMovie window.
The editing controls might not be as obvious to you. The scrubber bar is a visual "timeline" representation of whatever is being displayed in the Monitor, and it enables you to quickly move to any part of the clip being displayed.
The playhead is a marker that indicates the frame that is currently being displayed in the Monitor. As you play a clip, the playhead scoots along the scrubber bar to show you where you are in the clip at every point.
Next to the playhead, you see the timecode. The timecode numerically shows the location of the playhead in the format XX:YY:ZZ, where XX is the minute, YY is the second, and ZZ is the frame number currently being displayed. In Figure 3.2, you can see that the timecode is 01:56:05; this means that the playhead is 05 frames into the 56th second of the second minute of the selected clips.
More Frames than Seconds
Remember the flip books that you used to play with? That is what a movie really is; it is a series of images that "flip" across your screen to give the illusion of motion (which also explains why movies were originally called moving pictures). The rate at which images (called frames in video lingo) change determines how smoothly the motion in the video appears. The higher the frame rate (measured in frames per second and abbreviated as fps), the smoother the video is. Because higher frame rates mean that your computer must handle more information in a given amount of time, higher frame rates also require more computing power and larger file sizes. What is a good frame rate? If your video has about 30 frames per second, it plays smoothly when you watch it. Depending on how "fast" the action is, you might get by with fewer frames per second, but in most cases 30 fps is a good target.
The crop markers enable you to select frames while you edit the clip being displayed in the Monitor. The frames that are selected are indicated by the shaded area of the scrubber bar that is between the two crop markers.
More on Frame Rate
Technically, the frame rate you use for most of your movies is actually 29.97 frames per second. Should this discrepancy bother you? Not at all. Just think 30 frames per second, and you are close enough. The application handles the details for you. The "real" movies that you see in a theater use a frame rate of 24 frames per second, while the European standard is 25 fps. You will select the frame rate that you use for your movie when you output it.
The Camera/Edit mode switch is located just under the Monitor window (see Figure 3.2). You use Camera mode when you want to import clips from a DV camcorder that is connected to your Mac through FireWire. When you use Camera mode, the Monitor window changes so that it displays camera controls and the video that is stored on the camera (rather than within iMovie). You use Edit mode when you are editing clips within iMovie.