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Why is IMAX film bigger than ordinary cinema film?

A 70 mm IMAX film frame uses the strip sideways, with 15 perforations along its length. That orientation makes room for a much larger image than the five-perforation frames of conventional 70 mm projection. The unusual path through the projector starts to make sense when the film strip itself becomes the comparison.

3–5 min

Questions you could explore

  • How do the orientation and perforation count change the frame area of 70 mm IMAX film?
  • Why should film-based IMAX projection be distinguished from other systems using the IMAX name?

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Why is IMAX film bigger than ordinary cinema film? | Speech Topic | speaking.app