The Ken Burns effect is a type of panning and zooming effect used in video production from still imagery.
The name derives from extensive use of the technique by American documentarian Ken Burns. The technique predates his use of it, but his name has become associated with the effect in much the same way as Alfred Hitchcock is associated with the dolly zoom.
The feature enables a widely used technique of embedding still photographs in motion pictures, displayed with slow zooming and panning effects, and fading transitions between frames.
The technique is principally used when film or video material is not available. Action is given to still photographs by slowly zooming in on subjects of interest and panning from one subject to another. For example, in a photograph of a baseball team, one might slowly pan across the faces of the players and come to a rest on the player the narrator is discussing. By employing simulated parallax, a two-dimensional image can appear as 3D, with the viewpoint seeming to enter the picture and move among the figures.
The effect can be used as a transition between clips as well. For example, to from one person in the story to another, a clip might open with a close-up of one person in a photo, then zoom out so that another person in the photo becomes visible. The zooming and panning across photographs gives the feeling of motion, and keeps the viewer visually engaged.
Burns has credited documentary filmmaker Jerome Liebling for teaching him how still photographs could be incorporated into documentary films. He has also cited the 1957 National Film Board of Canada documentary City of Gold, co-directed by Colin Low and Wolf Koenig, as a source of inspiration for this technique. Winner of the Palme d'or at the Cannes Film Festival and nominated for an Academy Award,City of Gold used animation camera techniques to slowly pan and zoom across archival still pictures of Canada's Klondike Gold Rush.