720p/1080i/1080p High-definition video recording standards that refer to the vertical resolution, or the number of horizontal lines on the screen — either 720 or 1080 lines. Seven hundred twenty horizontal lines translate to a width of 1280 pixels, and 1080 lines translate to a width of 1920 pixels. The p stands for progressive scan, which displays the video frame all at once. The i stands for interlaced, an analog compression scheme that allows 60 frames per second (fps) to be transmitted in the same bandwidth as 30 fps by displaying 50 percent of the video frame at a time.
Adobe RGB A color space that encompasses most of the gamut of colors achievable on commercial printers, or approximately 50 percent of the visible colors specified by the International Commission on Illumination (CIE).
AE See automatic exposure (AE).
angle of view The amount of area covered by a lens or viewfinder, measured in degrees. Shorter or wide-angle lenses and zoom settings have a wider angle of view. Longer or telephoto lenses and zoom settings have a narrower angle of view.
aperture The lens opening through which light passes. The mechanism is an iris diaphragm of several blades that can be continuously adjusted to vary the diameter of the opening. Aperture is expressed in f-numbers such as f/8 and f/5.6.
artifact An unintentional or unwanted element in an image caused by an imaging device, or resulting as a byproduct of image processing, such as compression.
artificial light The light ...