film speed

noun, Photography

speed (def 5a).

Origin

1910-15

Examples from the web for film speed

So obviously you'd want to maximize what, back then, was a relatively slow film speed.
The general rule is the slower the film speed, the higher the quality of slide or negative.
Because of the film speed these actions appear faster than they actually were.
Choose the best film speed for various lighting and subjects.
In my case, heart valves, or in a non-medical area film speed or suture strength.
In this case, recycle time limitations would apply, but film speed requirements would be greatly relaxed.
Without a light meter, the photographer must estimate the correct exposure from the sunlight available and film speed used.

British Dictionary definitions for 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