A transition is an animated effect that eases – or emphasizes – the passage from one clip to the next. Fades, wipes and dissolves are common types of transition. Others are more exotic, and may even involve sophisticated 3-D graphics.
Transitions are stored in their own section of the Album. To use a transition, drag it from the Album into the Movie Window and drop it beside any video clip, theme clip or still image. You can also apply transitions directly to audio clips.
A series of transitions (the icons between the video clips) in Storyboard view.
In Timeline view, you can drop the transition on either the main video track, the overlay track, or the title track. On the video track, the transition provides a bridge between two full-screen clips (or between one clip and blackness if the transition has only one neighbor, as at the beginning of the movie). On the overlay and title tracks, the transition bridges two neighboring clips (or one clip and transparency).
Diagram: Five snapshots from the life of a 2-second diagonal wipe transition.
If a transition is to last for two seconds (the default transition duration in a fresh Studio installation), the second clip begins to run two seconds before the first clip is finished. At the outset, only the first clip is visible; by the end, the second clip has completely replaced the first. The details of what happens in between, as the first clip is gradually removed and the second gradually appears, depend on the transition type. Since the video clips overlap, the total duration of the pair of clips is reduced by the duration of the transition.
Here is the same transition as above, this time using actual video. For clarity, the transition boundary in the three center frames has been emphasized in white. Both clips continue to run while the transition is in progress.