The Purpose of B-roll

In my other posts, I briefly touched on the term "B-roll" without much explanation. However, I now seek to rectify that error by explaining what B-roll actually is and what it means to go out and film it.

The term originates from when 16mm film was produced using original negatives. Editors would have to match up the workprint with a secondary or B-roll of negatives. In multiple cases the term "B-roll" was used to describe a literal second roll of film that could be used to assist the editors of films in creating fade and dissolve effects.

However, in interviews and documentary films, the term "b-roll" is used to refer to any sort of secondary footage in the film. This secondary footage is used in turn with the footage of the person being interviewed to either eliminate unwanted content or really emphasize what the interviewee is talking about.

B-roll is used as an editing tool.

Sometimes it can hide when a camera zooms in by showing some B-roll in between the wide shot and the close up.

While other times, B-roll can be used to remove some of the interviewee's verbal tics from the video and make their delivery more succinct. Since, the audio and visual aspects of an interview are recorded independently,film makers can still use a clip they like even if the subject messes up one part of the delivery or if they didn't deliver those tidbits in that exact order. Furthermore, the B-roll can add context to the subject's remarks.

But what do filmmakers look for when they are compiling B-roll?

Variety. Of course, shots that are intended to add context are planned out but most of the B-roll that i have personally seen collected was collected out of circumstance and opportunity. The more B-roll the camera men recorded: the more options the editor has when putting together the final project. Variety means that not only are they looking for a bunch of shots of different objects but also shots from different perspectives. This fact led to an interesting video of Evan briefly being wheeled around in a wheelchair to capture a smooth and complete shot of the hospital.

However, that video also demonstrates how documentary and promotional filmmakers not only have to capture their surrounding is real time, but also have to improvise ways to get the shots they want on set.