Partial reversal of an image produced by brief exposure to light part-way through a normal development process.
Regularly repeated measurements of small parts of a larger construct, such as an image, made with a view to reconstituting the whole from the information collected. This is the key process in digitization.
The richness or vividness of a colour. A poorly saturated colour approaches grey; a fully saturated colour cannot be made more vivid. Colour is characterized by hue, saturation and lightness.
Device for digitizing film-based images (film scanner) or paper-based images (flat bed scanner).
An attachment designed to be placed in front of a light source to reduce the intensity of its output.
An analogue image created from a first-generation or original analogue image, and consequently of slightly lower quality eg a print made from a negative or transparency. Copied digital images are generally identical and hence free from generational decay.
A rather subjective quality attributed to images displaying good contrast, and clear and distinct reproduction of detail.
The period between pressing the shutter release and the moment the shutter opens, particularly in a digital camera.
An autoexposure mode that allows the user to select a particular shutter speed manually and leaves the camera to select a corresponding aperture.
In general, the period of time during which the blades of a shutter expose a film or sensor to light.
A highly absorbent compound, usually white granules, used to reduce humidity. It is commonly placed in sealed bags containing equipment or film to keep the air dry.
A filter that absorbs ultraviolet and a little blue light. Used to remove ultraviolet haze and improves the contrast of a distant scene.
A mounted transparency suitable for projection. Colour reversal film is therefore commonly known as "slide film".
A single-lens reflex camera featuring a single interchangeable lens through which, via a mirror and perhaps a pentaprism, a photographer is able to view an image. The mirror flips out of the light path to reveal the film or image sensor when the shutter is released.
Broadly, the reversal of tones apparent in grossly over-exposed images (such as those of the sun).
The relative sensitivity of a medium to electromagnetic radiation as a function of the wavelength or frequency of the signal.
An exposure meter that measures reflected light from a very restricted field of view eg 1o. It has a viewfinder to facilitate accurate alignment, and a small telescope to channel light to the sensor.
A lens having a focal length approximately equal to the diagonal of the camera's film format, or a field of view comparable with that of the human eye ie about 45o.
Devices designed to hold digital data typically from a computer or digital camera - eg CompactFlash card or DVD.
The fastest shutter speed with which flash output is fully synchronised with the period of exposure.