Often when I talk with people who are not involved in the video industry I’m asked to explain a lot of the terminology we use. In this blog I’ll attempt to explain B roll
The term B roll is the opposite of the seldom used term A-roll. A-roll being your main footage such as and interview while B-roll is the secondary footage that usually supports the main footage.
These terms stems from the analog linear editing days of film or video tape. In order to transition between two different piece of footage they had to be on separate film rolls or video tapes called A-roll and the B-roll.
B-roll is alternative or supplemental video footage that is intercut with the your main shots. It’s also known as a cutaway where you visually interrupt or literally cut away from your main shot to an alternate shot. For instance, when you have an interview with someone describing how they test blood samples in a laboratory, to make it more visually interesting and informative you cutaway to B-roll of someone actually testing a blood sample in a lab.
When a video is created it is usually editied together from a series of shorter pieces of dialogue from an interview that are strung together in a linear fashion. If you listen with you eyes closed it sounds like a continuos narrative piece. When you watch it you will see the that the characters movement jumps around because of the pieces that were removed or the rearranged. These edits are called jump cuts. They have become quite popular on social media videos but are not suitable for every style of video.
B-roll is used to cover those jump cuts. The effect is that dialogue will sound more natural and consistant because the B-roll hides the cuts. An bonus is that the B roll can support or enhance the narrative with a second stream of visual content.