Apple MB673Z/A User Manual - Page 654

flash A device either on or attached to the camera that emits a brief, intense burst of light when the shutter release button is pressed. Flashes, synchronized with the shutter, are used to obtain a correctly exposed image in low-light situations. See also exposure, external flash, fill-in lighting, hot shoe. flat The lack of density in an image when the contrast is too low. See also contrast, density. focal length The distance from the rear nodal point of the lens to the point where the light rays passing through the lens are focused onto the image plane-the digital image sensor. Focal lengths are measured in millimeters (mm). folder A type of container in the Aperture library used to organize projects and albums within projects. Folders do not contain images. See also album, library, project. foreground The area of the image between the subject and the camera. See also background, depth of field. format a. File format: A specific method of encoding information. Most well-known file formats, such as TIFF and PNG, have published specifications. b. Disk formatting: The preparation of a hard disk or other storage medium for use with a file system. For example, disk drives used with Mac OS X use the Mac OS Extended format. See also JPEG, PNG, PSD, TIFF, vault. frame The border of an image. Frame can also be used as a verb to describe the process of constructing a composition within a specific image area. See also crop. frontlighting A light source, emanating from the direction of the camera, that faces toward the subject. See also backlighting, sidelighting. f-stop The ratio of the focal length of the lens to the diameter of the opening of the aperture. See also aperture. Full Screen view A workspace view in Aperture with minimal user interface, used to view full-screen images with the least amount of light and color interference. See also Browser & Viewer view, Browser Only view, filmstrip, HUD. Full Screen view toolbar A collection of buttons and tools, grouped by function, located at the top of the screen in Full Screen view. See also toolbar. gamma A curve that describes how the middle tones of an image appear. Gamma is a nonlinear function often confused with brightness or contrast. Changing the value of the gamma affects middle tones while leaving the whites and blacks of the image unaltered. Gamma adjustment is often used to compensate for differences between Macintosh and Windows video cards and displays. The Mac Standard gamma is 1.8; the PC Standard is 2.2. 654 Glossary