What is the advantage of the anamorphic lens?
Advocates of the 2.35 concept often point to three advantages to be gained from the use of an anamorphic lens. First, in theory it allows you to use the full light output of the projector. When a 16:9 projector is displaying a 2.35 film in its normal aspect ratio, it does so by placing black bars above and below the image. Those black bars amount to about 25% of the total picture area, which means that 25% of the potential light output of the projector is being blocked. By stretching the 2.35 image vertically to take the full height of the display, the black bars are eliminated and the total light output of the unit is being used. The anamorphic lens then brings that total light output into use by stretching it across the 2.35 screen. This argument does not take into account the optical properties of the projector’s zoom lens. Let’s suppose that instead of using the anamorphic lens, you simply use the projector’s zoom features to increase the size of the 2.35 image to fill the screen.
