film speed

noun Photography.

speed(def 5a).

Origin of film speed

First recorded in 1910–15

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for film speed

film speed

noun

the sensitivity to light of a photographic film, specified in terms of the film's ISO rating

the rate at which the film passes through a motion picture camera or projector

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