https://www.nfsa.gov.au/sites/default/files/2025-02/Colour%20TV%20Mega%20Menu%203%20TVs_1000x745%20px.jpg
F-stop
F-Stop or f-number is the ratio of aperture diameter to focal length of a lens, giving an indicator of the light-gathering power of the lens.
The larger the f-number, the smaller the lens opening, i.e. a number of f2.8 indicates a larger aperture than f4.
A T-stop is a lens marking which indicates the true light transmission of the lens at a given aperture as opposed to the approximate light transmission indicated by the conventional f-stop marking. Often found on cinema camera lenses.
The National Film and Sound Archive of Australia acknowledges Australia’s Aboriginal and Torres Strait Islander peoples as the Traditional Custodians of the land on which we work and live and gives respect to their Elders both past and present.