Nest sequences

You can nest sequences within sequences—to any depth—to create complex groupings and hierarchies. You can nest a sequence into another having a different timebase, frame size, and pixel aspect ratio settings. A nested sequence appears as a single, linked video/audio clip, even though its source sequence may contain numerous video and audio tracks.

You can select, move, trim, and apply effects to nested sequences as you would to any other clip. Any changes you make to the source sequence are reflected in any nested instances created from it.

The ability to nest sequences enables you to employ a number of time‑saving techniques and to create effects that otherwise would be difficult or impossible:

• Reuse sequences. When you want to repeat a sequence—particularly a complex one—you can create it once, and then simply nest it in another sequence as many times as you want.

• Apply different settings to copies of a sequence. For example, if you want a sequence to play back repeatedly but with a different effect each time, just apply a different effect to each instance of the nested sequence.

• Streamline your editing space. Create complex, multilayered sequences separately; then add them to your main sequence as a single clip. This not only saves you from maintaining numerous tracks in the main sequence, but also potentially reduces the chances of inadvertently moving clips during editing (and possibly losing sync).

• Create complex groupings and nested effects. For example, although you can apply only one transition to an edit point, you can nest sequences and apply a new transition to each nested clip—creating transitions within transitions. Or you can create picture‑in‑picture effects, in which each picture is a nested sequence, containing its own series of clips, transitions, and effects.

When nesting sequences, keep in mind the following:

• You can’t nest a sequence within itself.

• Actions involving a nested sequence may require additional processing time, because nested sequences can contain references to many clips, and Adobe Premiere Pro applies the actions to all of its component clips.

• A nested sequence always represents the current state of its source. Changing the content of the source sequence is reflected in the content of nested instances. Duration is not directly affected.

• A nested sequence clip’s initial duration is determined by its source. This includes empty space at the beginning of the source sequence, but not empty space at the end.

• You can set a nested sequence’s In and Out points as you would other clips. Trimming a nested sequence does not affect the length of the source sequence. Also, subsequently changing the source sequence’s duration does not affect the duration of existing nested instances. To lengthen the nested instances and reveal material added to the source sequence, use standard trimming methods. Conversely, a shortened source sequence causes the nested instance to contain black video and silent audio (which you may need to trim off the nested sequence).