August 21, 2007 by EH Staff
Could we have a more intimidating technical term? You may encounter this jumble of letters in articles on video projector technology and on the back of DVD cases.
Today you’ll often see “anamorphic” used when describing the technology that enables superwide CinemaScope pictures to be viewed on a wide screen. So any discussion of this must start with aspect ratios, or the general shape in width to height, of a video display. Traditional squarish TV is 4:3, or four units in width to every three units in height. Widescreen HDTV is 16:9, also known as 1.78:1. Most movies are shot in the slightly wider format of 1.85:1. CinemaScope, which many blockbuster movies are shot in, is an even wider 2.35:1. Get it?
The difference in format shapes explains why you often see black bars, called letterboxing, on the top and bottom of your screen when watching a movie in a format that’s wider than your display.
An anamorphic DVD—often labeled as “Enhanced for widescreen” or “Enhanced for 16:9” allows for the image to be stretched to fill more of the screen. The term “anamorphic” doesn’t refer to the stretching, however. It actually refers to the squeezing of a picture shot in a widescreen format and then squished into the more squarish TV format on the DVD. (Originally, the term referred to squeezing a widescreen picture to fit onto 35mm film.) Anyway, a widescreen TV can then take that image and stretch it to fill most of the space, usually with narrower black bars. The result not only is a bigger image to view, but one with a higher resolution, for reasons we don’t have the space to go into here.
An anamorphic lens attached to a projector works in a similar way. First, the squished image is scaled to fill the height of the screen so that everyone would be appear unnaturally tall and skinny. But before you ever see the world of tall and skinny people, the anamorphic lens stretches the picture horizontally to fill the width of the screen, and everyone looks normal. The result is a big, wide picture with no more nasty black bars. This also requires a special screen that’s wide enough for the image.
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