A number that indicates the relative size of the opening of the lens (aperture) and written, for example, as f/16. Because the number is obtained by dividing the focal length of a lens by it's effective aperture, the larger the aperture, the smaller the f-number. In the conventional series, each number represents an aperture that admits half as much light as the preceding one. Thus f/16 lets half as much light as a lens opened to f/11.

A computer document.

A flash technique used to brighten deep shadow areas, typically outdoors on sunny days. Some digital cameras include a fill flash mode that forces the flash to fire, even in bright light.

Slang for shooting a picture. Example: I pressed the shutter button to fire.

A type of cabling technology for transferring data to and from digital devices at high speed. Some professional digital cameras and memory card readers connect to the computer over FireWire. FireWire card readers are typically faster than those that connect via USB. Also known as IEEE 1394, FireWire was invented by Apple Computer but is now commonly used with Windows-based PCs as well.

Area in an image closer than the main subject.

This is the colour that is used when painting, filling, and creating text.

Completely erasing and resetting a camera's memory card. This is usually done as a quick way to erase a full card that you want to reuse or to attempt to fix a card that can't be recognized by the digital camera.

Colour printing with cyan, magenta, yellow, and black inks.

Frames per second. Used to describe how many frames can the motor drive or winder can handle automatically on winding per second consequently. Also apply to areas like video, animations, movie cameras.

A mathematically generated pattern that is reproducible at any magnification or reduction.

One picture on a roll of film.

An area in RAM memory set aside to specifically hold the data for the screen display.

Pattern of a special form of condenser lens consisting of a series of concentric stepped rings, each ring a section of a convex surface which would, if continued, form a much thicker lens. Used on focusing screens to distribute image brightness evenly over the screen.

This occurs when a digital image is artificially sharpened. The term usually refers to a white fringe that is apparent on the edges of objects in the picture. Fringing can also occur as a result of compression.