Anamorphic Lens
A lens containing cylindrical elements that squeeze a wide field horizontally onto a standard frame, to be unsqueezed on projection.
Formula / rule
Desqueeze = width × squeeze factor
Measured in
squeeze ratio (e.g. 1.33×, 2×)
In depth
Anamorphics were invented to fit widescreen cinema onto ordinary 35 mm film, but they survive for their signature look: oval bokeh, horizontal blue flares and a shallow, stretched rendering that spherical lenses cannot imitate. The squeeze also means the lens uses more of the sensor's height, improving resolution over simply cropping a spherical image.
Examples in practice
A 2× anamorphic on a 4:3 sensor desqueezes to a 2.66:1 cinemascope frame with characteristic streaked highlights.