Todd-AO was a widescreen film format developed in the mid 1950s. It was co-developed by Mike Todd, a flamboyant Broadway producer, with American Optical Company. Unlike Cinerama, the process required a single camera and one set of lenses. Four kinds of lenses (35mm to 56mm, 63mm, 65mm, or 70mm) covered -128, 64, 48, 37 degree field of view. Films were shot in 65mm negative and the images then transferred to 70mm prints (to accommodate sound tracks) for projection. The aspect ratio of this format was 2.35:1 or 2.20:1.
The original version of the Todd-AO process used a frame rate of 26 frames per second, slightly faster than the 24 frames per second that was (and is) the customary standard. The difference does not seem great, but the sensitivity of the human eye to flickering declines steeply with frame rate and the small adjustment made the film appear noticeably less flickery, steadier, and smoother than standard processes.
A handful of epics and musicals of the 1950s and 1960s were shot in this format, including Oklahoma, South Pacific and Around the World in 80 Days.
A number of spectacular widescreen films made in the 1970s and 1980s, including Dune and Logan's Run bore the Todd-AO trademark. They were filmed on 70mm, and 70mm prints were projected in the big-city first-run houses. They did not, however, use the original Todd-AO technical processes. As with Cinerama, aficionados argue over which films should be considered "true" Todd-AO films. (2001: A Space Odyssey is especially confusing; its New York premiere was in the Todd-AO Theatre and some of the technical work was done by Todd-AO; it originally carried a Cinerama credit; and was actually filmed in Super Panavision 70).
- Internet Movie Database listing of films shot in Todd-AO (http://www.imdb.com/SearchTechnical?PCS:Todd-AO)
- Todd-AO information from in70mm.com (http://www.in70mm.com/todd_ao/)
- WideScreen Museum history of Todd-AO (http://www.widescreenmuseum.com/widescreen/wingto1.htm)