A-roll is your main footage — the interview, the talking head, the primary action. B-roll is everything supplementary shot to support it. Skilled use of B-roll is often what separates amateur-feeling edits from polished ones.
What B-Roll Does For an Edit
B-roll serves several jobs at once:
- Covers jump cuts — placing B-roll over the moment you cut dead air in a talking-head clip hides the jump entirely, since the viewer's eye is on the B-roll, not the speaker's face
- Illustrates what's being said — if someone describes a process, showing it happening is more engaging than watching them describe it
- Controls pacing — B-roll shots are often shorter than A-roll, so cutting between them naturally speeds up a section
- Adds production value — varied shots (wide, close, detail) make a video feel more crafted than a single static angle
Shooting (or Sourcing) B-Roll With Intent
The best B-roll is shot with a specific edit in mind — a close-up of hands typing while a narrator discusses a feature, a wide establishing shot before a location-based story. If you're editing footage you didn't shoot, review all of it before cutting to identify usable B-roll rather than searching mid-edit, which breaks your flow.
J-Cuts and L-Cuts
These are the two fundamental techniques for blending audio and video across a cut:
- J-Cut — the audio from the next clip starts before its video appears (you hear the next scene before you see it). Named because the edit shape resembles the letter J on the timeline: audio leads.
- L-Cut — the audio from the current clip continues after its video has cut away to something else (you keep hearing a speaker while looking at B-roll of what they're describing). Named because the shape resembles an L: video leads, audio trails.
To create either, unlink the clip's audio and video (right-click > Unlink), then drag just the audio or just the video portion independently so their edit points no longer align.
L-cuts, in particular, are the standard technique for cutting to B-roll during an interview — you hear the person continue talking while watching the footage they're describing, which feels far more natural than a hard cut to silence-then-B-roll.
Building a Montage
A montage compresses time or covers a lot of ground in a short span — a training sequence, a "day in the life," a product's key features. A few principles:
- Establish rhythm early — the first few cuts set an expectation for pace; keep it consistent unless you're deliberately building to a change in energy
- Cut to music — align cuts to beats or musical phrases so the edit feels intentional rather than arbitrary (see the timeline's audio waveform to find beat markers, or add markers manually while listening)
- Vary shot types — avoid stringing together several similar shots (three wide shots in a row) back to back; alternate wide, medium, and close framing
- Let some shots breathe — not every cut needs to be fast; a slightly longer hold on a strong shot gives the montage texture
Match Cuts
A match cut connects two shots through visual or motion similarity — a spinning wheel cutting to a spinning fan, a hand closing a book cutting to a hand closing a laptop. These require planning ahead of the edit (ideally at the shoot) but create some of the most memorable transitions in a video when they land well. Don't force them; a match cut that requires explaining doesn't work.