John Richard Chambers was an artist and filmmaker. Born in London, Ontario, Chambers' painting style shifted from surrealist-influenced to photo-realist-influenced. He used the term "Perceptual Realism" and later "perceptualism" to describe his style. He began working with film in the 1960s, completing six by 1970. Stan Brakhage proclaimed Chambers' The Hart of London as "one of the greatest films ever made."