Open Matte
From DigiWiki
Open Matte is a filming technique whereby a film is shot in full-frame aspect ratio and the widescreen version of the film is created by matting (cutting off) the top and buttom of the picture. The full-frame version of the film, in this case, is the original print and contains more information than the widescreen version of the film - the opposite is usually true when it comes to widescreen prints and the Pan & Scan technique.
For example, the Back to the Future Trilogy was shot in open matte format, and early editions of the DVD has incorrect matting applied to the widescreen version.
