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The Todd-AO process uses two separate film stocks; a 65 mm negative is used during production and then used to produce the 70 mm positives for distribution. The sprocket hole perforations on the two are the same, and the positives are printed using contact printing with the negatives centered on the larger 70 mm film. Contact printing was used on prints that were to be "double system", using a separate, synchronized 35 mm full-coat magnetic film for the 6 sound tracks, in addition to the 70 mm film for the picture. The much more common 70 mm release prints used a slightly optically reduced picture [cite references], and placed four of the soundtracks on either edge outside of the perforations, and two more soundtracks inside the perforations, providing a total of six soundtracks, on a 7.5 mm magnetic surface. Todd-AO soundtracks were very high fidelity, and could still compete with modern digital tracks above 40 kHz. Speaker layout was Left, Left-center, Center, Right-center, Right, and mono Surround.^[7] Even though there were no subwoofers in theaters in those days, Todd-AO delivered high-impact bass using crisp-sounding horn-loaded speakers. Four lens options covered a 128, 64, 48 or 37 degree field of view. The aspect ratio of this format was 2.20:1.

Both film sizes had been used in the past, in the 70 mm Fox Grandeur process in 1929–1930, but Todd-AO's physical format was not compatible with this format. The use of 65 mm photography and 70 mm printing became the standard adopted by others: Super Panavision 70 (essentially the Panavision company's version of Todd-AO) and Ultra Panavision 70 (the same mechanically, but with a slight 1.25:1 anamorphic squeeze to accommodate extremely wide aspect ratio images) are both 65/70 processes. The Soviet film industry also copied Todd-AO with their own Sovscope 70 process, identical, except that both the camera and print stock were 70 mm wide.

The IMAX format also uses 65 mm camera and lab film to create 70 mm prints for projection (also known as the 65/70 mm process); conforming to the pitch and perforation standard for 70 mm Todd-AO film. However, the IMAX frame is 15 perfs wide and runs horizontally through the projector, whereas the Todd-AO frame is only 5 perfs high and runs vertically through the projector.^[8]

The original version of the Todd-AO process used a frame rate of 30 frames per second, faster than the 24 frames per second that was (and is) the 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 gave the film noticeably less flicker, and made it steadier and smoother than standard processes. The original system generated an image that was "almost twice as intense as any ever seen onscreen before, and so hot that the film has to be cooled as it passes through the Todd-AO projector".^[9]

Only the first two Todd-AO films, Oklahoma! and Around the World in Eighty Days, employed 30 frames per second photography. Because of the need for conventional versions at 24 frames per second, every scene of the former film was shot twice in succession: once in Todd-AO and once in 35 mm CinemaScope. The latter film was shot with two 65 mm Todd-AO cameras simultaneously, the speed of the second camera was 24 frames per second for wide release as optical reduction prints. All subsequent Todd-AO films were shot at 24 frames per second on a 65 mm negative and optically printed to 35 mm film as needed for standard distribution.^[10] In all, around 16 feature films were shot in Todd-AO.

Todd-AO was developed and tested in Buffalo, New York, at the Regent Theatre. Richard Rodgers and Oscar Hammerstein II went there to see Todd-AO test footage, which led them to approve its use for Oklahoma!. Ampex Corporation engineers were in charge of developing the Todd-AO sound system. Ampex would later go on to manufacture the sound system, including selectable four-track composite (CinemaScope), six-track composite (Todd-AO), four-track interlocked, six-track interlocked or optical sound sources.

The Todd-AO Company also offered a 35 mm anamorphic process technically similar to 35 mm Panavision or CinemaScope. This may cause some confusion if a Todd-AO credit (not necessarily the more specific Todd-AO 35 credit) appears in some widescreen films made in the 1970s and 1980s. It becomes even more confusing as 70 mm prints were made for films which, unlike earlier pictures made in the process, were shown in multiplexes, like Dune and Logan's Run.

During the late 1970s through the early 1990s, 65 mm photography such as that used in processes like Todd-AO or Super Panavision became rare. However, some major films had 70 mm prints made by blowup from 35 mm negatives mostly for the benefit of six-track sound. These prints would typically play only in a few theatres in a few large cities while everyone else viewed the film in 35 mm. The advent of multichannel digital sound in the 1990s obviated these very expensive prints. "Blow-up" 70 mm prints also followed the Todd-AO layout, although in the case of films made with a 1.85:1 aspect ratio, it was retained in the 70 mm version, with the sides of the 70 mm frame left black.

While Todd-AO was intended to be "Cinerama out of one hole", the extreme wide-angle photography and projection onto a very deeply curved screen (which is what that would imply) saw little use. Most Todd-AO theatre installations had only moderately curved screens and the extreme wide-angle camera lenses were used only on a few shots here and there. Todd-AO films made after 1958 used a conventional flat widescreen, and resembled ordinary films, except for their greater clarity and six-track stereo sound. A variation on Todd-AO called Dimension 150 did, however, make use of Cinerama-like deeply curved screens. Only two films were made in Dimension 150 – The Bible: In the Beginning..., directed by John Huston, and Patton, starring George C. Scott. In some venues, however, Todd-AO and Dimension 150 films received their first run in Cinerama theatres in order that they be shown on a deeply curved screen – such as the first Atlanta showings of The Sound of Music.^[11]

Todd-AO films were closely associated with what was called roadshow exhibition. At the time, before multiplex theatres became common, most films opened at a large single screen theatre in the downtown area of each large city before eventually moving on to neighborhood theatres. With the roadshow concept, a film would play, often in 70 mm at a movie palace downtown theatre exclusively, sometimes for a year or more. Often a "hard ticket" policy was in effect, with tickets sold for specific numbered seats, and limited showings per day. Most Todd-AO films through the late 1960s, including Those Magnificent Men in Their Flying Machines and The Sound of Music, were initially shown on a roadshow basis.

In some US cities, individual theaters were converted for use in the 1950s as dedicated Todd-AO "Cinestage" showplaces. These theaters showed exclusive roadshow engagements of Todd-AO and other 70 mm films on large, deeply curved screens. They included the Rivoli Theatre in New York City,^[12] the Cinestage Theatre in Chicago^[13] and Hunt's Cinestage Theatre in Columbus, Ohio.^[14]

The roadshow era ended in the early 1970s, although a very few films (among them Gandhi) were shown in roadshow format after that.

In the 1970s, under the leadership of Dr. Richard Vetter, Todd-AO made an attempt to compete with Panavision in the 35 mm motion picture camera rental market. The company built a series of anamorphic lenses in the 2.35:1 scope format, and owned several camera bodies (Mitchell and Arriflex) that they would provide with the lens package. Films produced in Todd-AO 35 include Conquest of the Planet of the Apes, Conan the Barbarian, Mad Max, Dune and Logan's Run.^[15]

By the mid 1980s the venture was moribund, and was finally abandoned in 1992. Eventually all of the Todd-AO cameras and lenses, both 35 mm and 65 mm (70 mm), were sold to Cinema Products in Los Angeles. The 35mm anamorphic lenses are now in the rental inventory of Keslow Camera.