aspect ratios of films are usually normalized to one. To make comparisons between video displays and films easier, the ratios for displays can also be normalized to one. Hence 16:9 becomes 1.78:1 and 4:3 becomes 1.33:1.
Aspect Ratios of Films
Nearly all films made from the 1920s through the early 1950s used an aspect ratio of 1.37:1. To compete against the threat of television, movie studios began adding features such as color and a wider (larger) picture.
Now nearly all films are made in a widescreen format. The most commonly used aspect ratios today are 1.85:1 and 2.35:1. This wider picture allows for more dramatic and creative visual compositions.
Matching Film to Display
When the aspect ratio of the film closely matches the aspect ratio of the display, the film can easily be viewed as the director intended. This happens when watching a 1.37:1 film on a 1.33:1 standard video display or when watching a 1.85:1 film on a 1.78:1 widescreen video display, as there is only a negligible mismatch. But when there is a significant mismatch between the aspect ratios of the film and video display, some action must be taken to allow the film to be viewed without distortion.
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