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Single‑ and double‑sided transitions

Transitions are typically double‑sided—they combine the last video or audio material from the clip before the cut with the first material from the clip right after the cut. You can, however, apply a transition to an individual clip so that it affects only the beginning or end of the clip. A transition applied to a single clip is called single‑sided. The clip can be immediately adjacent to another clip or sitting by itself on a track.

Using single‑sided transitions, you have more control over how clips transition. For example, you can create the effect of one clip departing using the Cube Spin transition, and the next clip fading in using Dither Dissolve.

Single‑sided transitions fade to and from a transparent state, not to and from black. Whatever is below the transition in a Timeline panel appears in the transparent portion of the transition (the portion of the effect that would display frames from the adjacent clip in a two‑sided transition). If the clip is on Video 1 or has no clips beneath it, the transparent portions display black. If the clip is on a track above another clip, the lower clip is shown through the transition, making it look like a double‑sided transition.

View full size graphic
Single‑sided transition with clip beneath it (left) compared to single‑sided transition with nothing beneath it (right)

If you want to fade to black between clips, use the Dip To Black dissolve. Dip To Black doesn’t reveal any underlying clips; it always fades to black.

In a Timeline panel or the Effect Controls panel, a double‑sided transition has a dark diagonal line through it, while a single‑sided transition is split diagonally with one half dark and one half light.

Types of transitions 

A.
Double‑sided transition using duplicate frames

B.
Double‑sided transition

C.
Single‑sided transition

Note: If a double‑sided transition must repeat frames (rather than use trimmed frames), the transition icon contains additional diagonal lines. The lines span the area where it has used the repeated frames. (See Clip handles and transitions.)