Optical compression system — horizontal image data squeezed 2x by anamorphic lens, then unsqueezed in post. Signature bokeh shapes, vertical lens flares, 2.39:1 aspect ratio.
Anamorphic optics compress the horizontal image by a factor of 2 — which on set means: you shoot with a special front lens that squeezes the image sideways. The camera thus captures less horizontal information per millimeter of sensor, but compensates for this through the extreme focal length shortening of the anamorphic lens. In post-production, the material is stretched back to its natural aspect ratio (usually 2.39:1). The result: a characteristic optical signature that has been equated with cinema since the 1950s.
On set, handling differs from spherical systems. The anamorphic lens has a shorter effective focal length horizontally than vertically — a 40mm anamorphic can feel like a 20mm horizontally, but like a 40mm vertically. This makes composition tricky: your vertical lines remain stable, but you need to account for significantly more space horizontally. The bokeh appears oval, not round — especially visible at wide apertures (T2.0 to T1.3 are typical). Point light sources produce vertical lens flares, long and elegant, not the round flares of modern spherical lenses. These flares are not a flaw, but part of the aesthetic — everyone knows them from Hollywood classics.
The practical challenges: Anamorphic lenses are slow in terms of light transmission because the optical construction is complex. You need strong lighting or higher ISO values. The depth of field is shallower at the same aperture compared to spherical lenses (because the effective horizontal aperture is larger). For focus pulling, your 1st AC must account for the different focal length ratios — an error of a few centimeters becomes massively visible horizontally. Modern digital anamorphic lenses (Cooke, Zeiss Master Anamorphics) have better aberration control than older lenses, but even those have their charm if used intentionally.
The size and weight are considerable — anamorphic lenses require matte box support and larger follow focus systems. It becomes difficult on lightweight rigs (gimbal, drone). But for those who want that classic, large-format Cinemascope feeling, anamorphic optics are indispensable. Digital zoom solutions cannot optically replicate what physical light refraction achieves.