exposure meter

Device with light-sensitive cells that measures the intensity of the light striking or reflected by the subject to determine the correct exposure for a photo.

film speed scale

Graduated scale that shows the film’s sensitivity to light; it is expressed by the ISO or ASA number, where the higher the number, the more sensitive the film.

exposure-time scale

Graduated scale that shows the length of time a film should be exposed to light, which is determined by the shutter speed.

exposure correction scale

Graduated scale that shows changes made to exposure data when deliberately underexposing or overexposing a scene.

indicator needle

Thin metal bar that shows the brightness measured by light-sensitive cells on the exposure meter.

exposure value scale

Graduated scale that shows the amount of light to which the film should be exposed.

calculator dial

Rotating dial that adjusts the film speed.

aperture scale

Graduated scale that shows the diaphragm’s opening measured in f-stops (a high f-stop indicates a small opening).

cine scale

Graduated scale that shows the speed at which a motion picture film unwinds; it is expressed in frames per second.

light-reading scale

Graduated scale showing the intensity of the light striking or reflected by the subject.

diffuser

Translucent half globe used to measure the intensity of the light striking the subject to be photographed (incident light).