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Digital TV / Aspect Ratio

This film has been modified
from its original version.
It has been formatted to fit your screen.

Ever wonder about that little message means when you see it just before a Hollywood movie on your television?

You usually see that message because the movie was shot in a wider picture for the movie theater. When the studio released the home version they had to cut the sides off the images so that it would fit your TV screen. Our televisions use a different aspect ratio than widescreen movies. The aspect ratio of your old TV is 4 :3, which means it's a little wider than it is taller. For every 4 units of width our television screen stetches out 3 units of height. For example, if the width of the screen is 20 inches, its height is about 15 inches (20:15, or 4:3).

The current aspect aspect ratio used for television was originally developed by W.K.L. Dickson in 1889 while he was working at Thomas Edison's laboratories. Dickson was experimenting with a motion-picture camera called a Kinescope, and he made his film 1" wide with frames 3/4" high. This film size, and its aspect ratio, became the standard for the film and motion-picture industry because there was no apparent reason to change. In 1941, when the NTSC proposed standards for television broadcasting, they adopted the same ratio as the film industry. It made sense fifty years ago.

A Wider Screen[next]


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