prime lens

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 f2.8 to f1.2. The term can also mean the primary lens in a combination lens system.
Confusion between these two meanings can occur if context doesn't make the interpretation clear. People sometimes use alternate terms—primary focal length, fixed focal length, or FFL to avoid ambiguity.

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