Prime lens
camera lens with fixed focal length
In film and photography, a prime lens is a fixed focal length photographic lens (as opposed to a zoom lens), typically with a maximum aperture from f/2.8 to f/1.2. The term can also mean the primary lens in a combination lens system.
Confusion between these two meanings can occur without clarifying context. Alternate terms, such as primary focal length, fixed focal length, or FFL are sometimes used to avoid ambiguity.
As alternative to zoom lens
The term prime has come to mean the opposite of zoom—a fixed-focal-length, or unifocal lens.
While a prime lens of a given focal length is less versatile than a zoom lens, it is often of superior optical quality, wider maximum aperture, lighter weight, and smaller size. These advantages stem from having fewer moving parts, optical elements optimized for one particular focal length, and a less complicated lens formula that creates fewer optical aberration issues. Larger maximum aperture (smaller f-number) facilitates photography in lower light, and a shallower depth of field.
A normal lens or "normal prime" is a lens with a focal length about equal to the diagonal size of the film or sensor format, or that reproduces perspective that generally looks "natural" to a human observer under normal viewing conditions.
Traditional meaning as primary lens
The older, original meaning of prime lens is the main lens in a combination lens system.
Begin with the source’s own compact description: “Prime lens” is camera lens with fixed focal length. The dossier treats that line as a proposition to test through Prime, lens and camera, not as a finished interpretation.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Jun 1, 2026. The linked authority identifier is Q631962. None of the 0 selected statements returned an explicit reference.
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This entry incorporates text from “Prime lens” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.