Choosing the Right Aspect Ratio
What is aspect ratio, you ask? Aspect ratio is the ratio of the width of the screen to the height of the screen. Essentially, it describes the shape of the rectangle. Today the most popular aspect ratio for consumer video display is 16:9, which is the standard HDTV format. The numbers mean that the picture is 16 units wide for every 9 units in height.
Sometimes you will see the 16:9 aspect ratio referred to as 1.78:1, or simply 1.78. Why? Because 16 divided by 9 = 1.78. But it means the same thing. A 1.78 screen is 1.78 units in width for every unit of height.
If you are going to use a flatscreen HDTV for your home theater, you are stuck with the 16:9 format for better or for worse. Though they come in a wide variety of sizes, they are all 16:9 aspect ratio. But if you are planning to use a projector and screen, you have another option, which is 2.4:1, commonly known as the Cinemascope format. This is a wider format than standard 16:9. Many people prefer it because it matches the aspect ratio of a lot of movies being produced today.
Think about the black bars
Here is a simple fact of life: Videos and movies are made in a variety of different aspect ratios. There is no standard. So no matter what aspect ratio your screen is, you will always end up with black bars at the top and bottom of some material, and black pillars at the sides of other material. The only time you don’t get black bars is if you are viewing video or film shot in the format of the screen you are using–either a film done in 1.78 displayed on a 16:9 screen, or a movie shot in 2.4 on a 2.4 Cinemascope screen. In both of those cases, the screen frame will match the picture precisely, and no black bars will exist.
(By the way, we’re assuming you want to see the material you watch in its correct original aspect ratio, as the director created it. If you don’t, there are several ways to stretch, manipulate, or crop video images to get them to fill a 16:9 screen and eliminate the black bars.)
So in choosing between a screen aspect ratio of 1.78 vs. 2.4, you are really deciding how the various film and video formats will appear on your screen. For example, if you select a 16:9 screen, all of your 2.4 format movies will have black bars top and bottom. If you select a 2.4 screen, all of your 16:9 material will be “pillar-boxed” in the center of the screen with black columns on each side.
By Evan Powell
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