Apple MB673Z/A User Manual - Page 644

archive The process of storing image data on a permanent medium, such as optical media (CD or DVD). aspect ratio The ratio of height to width of the dimensions of a photograph. Common North American aspect ratios are 3.5 x 5, 4 x 6, 5 x 7, 11 x 14, and 16 x 20 inches. auto focus The system within the camera that automatically focuses the lens on a specific portion of the subject or scene. automatic bracketing A setting on many professional cameras that automatically brackets the exposure of the image. See also bracketing. background The area in the rear of the image that appears behind the subject. See also depth of field, foreground. backlighting A light source that faces toward the lens of the camera, emanating from behind the subject. Backlighting makes the outline of the subject stand out from the background, often resulting in a silhouette. See also frontlighting, sidelighting, silhouette. badge overlay A small icon Aperture places on an image to indicate that an adjustment, keyword, or other change has been applied to it. See also adjustment, keywords, offline. Bayer pattern color filter array A specific arrangement of red, green, and blue lenses attached to the surface of a digital image sensor. There are roughly twice as many green lenses as blue and red to accommodate how the human eye perceives color. See also charge-coupled device (CCD), complementary metal oxide semiconductor (CMOS), digital image sensor. bit depth The number of tonal values or shades of a color each channel in a pixel is capable of displaying. Increasing the bit depth of color channels in an image's pixels exponentially increases the number of colors each pixel can express. See also color channels, color depth. black point compensation Black point compensation ensures that black and white luminance values are appropriately scaled to fit within the range or gamut of the destination device (printer, paper, and ink). Using black point compensation helps prevent clipping in shadows because the blacks are scaled to fit within the gamut of the printer, paper, and ink. Black Point parameter An Exposure adjustment parameter in Aperture used to set the blacks in the image. See also Exposure adjustment. Blank setting A Secondary Viewer setting that sets the Secondary Viewer display to be a blank screen. See also display, Secondary Viewer. 644 Glossary