Many people argue that if you want a film in stereo you should shoot it in stereo. Yet many filmmakers do not want the physical size of an on set stereo rig, or they prefer to shoot film (ruling out stereo in camera, effectively) or want to use anamorphic lenses which are extremely difficult for stereo native capture. Even on a stereo film, lenses and situations often times render a single camera the only viable solution. Thus, even on films shot in stereo there may well be a need to convert some footage and that high quality conversion is an important tool in the box of any effects house.

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