Canon CanoScan FB 1200S User Manual - Page 63

Glossary A P P E N D I C E S Brightness The amount of light in an image when it is scanned. Increasing the brightness setting makes the entire image lighter, and decreasing the brightness setting makes the entire image darker. (p. 47) Contrast The degree of difference between the dark and light portions of a document being scanned. Raising the contrast of an image tends to sharpen it, lowering the contrast tends to blur it. (p. 47) Color (24-bit) Expresses a dot with 8-bits for each primary color for a total of 24 bits (8 bits x 3 colors = 24 bits). A dot can be expressed in up to 16.8 million distinct shades (2563=16.8 million) Color (36-bit) Expresses a dot with 12-bits for each primary color, red, green, and blue (RGB), for a total of 36-bits (12 bits x 3 colors = 36 bits). A dot can be expressed in up to 68.7 billion distinct shades (4,0963=68.7 billion) Dot The fundamental element of a letter, object or image. The number of dots per inch (dpi) determines the resolution (or density) of a letter, object or image. Gamma Correction The process whereby variations in color tones from the output of monitors, printers and other output devices are made consistent with the source (input) document. In Plug-in Module CS-S you can use the gamma value setting, or enter a gamma value directly, to set a value to match the gamma value for your monitor. Gamma values are expressed as numbers: 1 is the standard value, numbers lower than 1 brighten the output and numbers higher than one darken the output. A graph function, the tone curve (gamma curve), is also available in Plug-in Module CS-S to make adjustments to gamma values. Gamma Curve See the entry for Gamma Correction. Grayscale (8-bit) Expresses a dot in 256 shades of gray between white and black. Grayscale (12-bit) Expresses a dot in 4,096 shades of gray between white and black. 63 63