Canon LEGRIA FS36, User Manual

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Appendices
Dot
The fundamental element of a letter, object or image, which is arranged in
vertical and horizontal groups. When scanning a film, the number of dots
per inch (dpi) determines the resolution (or density) of a letter, object or
image.
Film Base Color
Color negative film that has been developed has an overall orange tint.
This is called the film base color. This tint is applied to the film to eliminate
unnecessary light and reproduce colors at their best. Each manufacturer
uses a slightly different film base color for each of their products. As a
result, the scanner must compensate for these differences to reproduce
colors faithfully.
Gamma Correction
A setting to make the brightness of image data consistent between the
original film (input value) and the computer display (output value) or any
further output devices, such as a printer. The relationship between the
input and output is called the gamma value. A value of 1 represents output
that equals the input. A gamma value of less than one, indicates that the
output is brighter than the original and values over one indicate that the
output is darker. The graphical representation of the relationship is called
the gamma curve (or tone curve).
(p. 65)
Gamma Curve
See gamma correction.
Grayscale
An (8-bit) image type utilizing only the brightness data from an image,
which is then expressed in black, white and 256 shades of gray.
Halftone
Color tones between the extremes of black and white. In black and white
images, halftones are simulated with dithering or diffusion techniques.
Histogram
A graph that shows the distribution of shadows and highlights in an image.
An image file contains data with varying brightness values. The brightness
values range from shadows to highlights, which are assigned values
ranging from 0 to 255.