The strength of light falling on a given area of surface. Measurable
by an incident-light (illuminance) meter.
meter: See Incident
light: Light emitted when
a substance is heated by electricity: for example, the tungsten
filament in an ordinary light bulb.
light meter: An exposure
meter that measures the amount of light incident to (falling on)
film: See Type
A film; tungsten film.
The farthest position of on the distance scale of a lens. It includes
all objects at the infinity distance (about 50 feet) from the lens
or farther. When the infinity distance is within the depth of field,
all objects at that distance or farther will be sharp.
The band of invisible rays just beyond red, which people perceive
to some extent as heat. Some photographic materials are sensitized
to record infrared.
film: A film such as Polaroid
Time-Zero that contain the chemicals needed to develop an image
automatically after exposure without the need for darkroom development.
A process increasing the darkness of an already developed image.
Used to improve negatives that have too little silver density to
make a good print or to increase the density of an existing print.
lens: A lens that can be
removed from a camera and replaced with another lens, usually of
a different focal length.
square law: A law of physics
stating that the intensity of illumination is inversely proportional
to the square of the distance between light and subject. This means
that if the distance between light is doubled, the light reaching
the subject will be one-quarter of the original.
A numerical rating that describes the sensitivity of a film to light.
The ISO rating doubles as the sensitivity of the film doubles.