To make full use of the available film, an anamorphic lens is used during recording; this lens effectively squeezes the picture horizontally so that (in the case of the common 2x anamorphosis lens) a frame twice as wide fills the available film area (Figure 2). Since a larger film area is being used to project the same picture, quality is increased. (The film frame itself is also very slightly larger.) The distortion introduced in the picture must be corrected when the film is played back, so another lens is used during projection that unsqueezes the picture to its correct proportions. It should be noted that the picture is not vertically manipulated in any way—the normal anamorphic process instead uses a horizontally-oriented element to squeeze the width only.
Other widescreen film formats (commonly 1.85:1 and 1.66:1) are simply cropped in vertical size to produce the widescreen effect, a technique known as masking or matting. This can occur either during filming, where the framing is masked in the gate, or in the lab, which can optically create a matte onto the prints.