This glossary is a work in progress, we will keep adding terms as we go...
Aperture (aka f/stop)
Lens opening. The hole or opening formed by the metal leaf diaphragm inside the lens or the opening in a camera lens through which light passes to expose the film. The size of aperture is either fixed or adjustable. Aperture size is usually calibrated in f- numbers-the larger the number, the smaller the lens opening. Aperture affects depth of field, the smaller the aperture, the greater is the zone of sharpness, the bigger the aperture, the zone of sharpness is reduced. The hole or opening formed by the metal leaf diaphragm inside the lens; controls amount of light and depth of field, prevents vignetting and reduces lens aberrations; the size of the aperture is indicated by its f-number, i.e., the ratio of the diameter of the opening to the focal length of the lens; a large aperture is indicated by a small numerical f-number.
Backlighting
Light coming from behind the subject, toward the camera lens, so that the subject stands out vividly against the background. Sometimes produces a silhouette effect. Always use something (a hand, a lens shade to avoid the light falls onto the lens - to avoid lens flares).
Color Balance
How a color film reproduces the colors of a scene. Color films are made to be exposed by light of a certain color quality such as daylight or tungsten. Color balance also refers to the reproduction of colors in color prints, which can be altered during the printing process.
Colour temperature.
Description of the colour of a light-source by comparing it with the colour of light emitted by a (theoretical) perfect radiator at a particular temperature expressed in kelvins (K). Thus "photographic daylight" has a colour temperature of about 5500K. Photographic tungsten lights have colour temperatures of either 3400K or 3200K depending on their construction.
CompactFlash
Most digital cameras with PC Card interfaces use a storage technology called CompactFlash. Standard supported by the CompactFlash Association. CompactFlash is ATA compatible and will fit into any Type II or Type III slot when used with a passive adapter.
Exposure
The quantity of light allowed to act on a photographic material; a product of the intensity (controlled by the lens opening) and the duration (controlled by the shutter speed or enlarging time) of light striking the film or paper. The act of allowing light to reach the light-sensitive emulsion of the photographic material. Also refers to the amount (duration and intensity) of light which reaches the film.
f/stop (aka aperture)
A fraction which indicates the actual diameter of the aperture: the "f" represents the lens focal length, the slash means "divided by," and the word "stop" is a particular f-number; for example, with a 50mm f/1.4 lens, the actual diameter of its maximum aperture is 50mm divided by 1.4 or 35.7mm; at f/2, the diameter becomes 50mm/2 or 25mm; at f/2.8, the aperture is 50mm/2.8 or 17.9mm across; as the numerical value of the f/stop increases, the aperture decreases in size.
ISO Speed
The international standard for representing film sensitivity. The emulsion speed (sensitivity) of the film as determined by the standards of the International Standards Organization. In these standards, both arithmetic (ASA) and logarithmic (DIN) speed values are expressed in a single ISO term. For example, a film with a speed of ISO 100/21° would have a speed of ASA 100 or 21 DIN. The higher the number, the greater the sensitivity, and vice versa. A film speed of ISO 200 is twice as sensitive as ISO 100, and half that of ISO 400 film.
Resolution
The ability of a lens to discern small detail; in photography, the image resolution in the final photograph depends on the resolving power of the sensitive emulsion and on that of the lensóthe two are not related, but the effective resolution is a function of both; for reasonably accurate photographic measurements of lens resolution, the sensitive material must therefore have a much greater resolving power than the lens.
Shutter
Blades, a curtain, plate, or some other movable cover in a camera that controls the time during which light reaches the film.
Shutter Priority
An exposure mode on an automatic or autofocus camera that lets you select the desired shutter speed; the camera sets the aperture for proper exposure. If you change the shutter speed, or the light level changes, the camera adjusts the aperture automatically.
Wide-Angle Lens
A lens that has a shorter focal length and a wider field of view (includes more subject area) than a normal lens.Also can explained as a lens whose focal length is shorter than the diagonal of the film frame; in 35mm photography, lenses shorter than 50mm; also referred to as a "short" lens.
Taken from: http://www.mir.com.my/rb/photography/glossary.
