Canon scanner CanoScan D660U User Manual

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Black-point
The darkest portion of an image scanned as Color or Grayscale. When
you click on the image with the Black-point eyedropper, all tones darker
than the selected sample tones are adjusted to black.
Brightness
The overall amount of lightness or darkness in an image. An image with
maximum brightness tends toward white; an image with minimum
brightness tends toward black. While contrast refers to the range and
number of tones in an image, brightness...

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Clear button
The button that removes the current image from the Preview Area.
Color Channels
The red, green, or blue components of a color image. Color images
contain 8 bits per pixel each for red, green, and blue channels, therefore
each pixel has 24 bits. If you are scanning a color image, you can change
the brightness and contrast of the individual red, green, and blue tones
in your image. The Master channel is a combination of the three.
Color Matching...

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Crop
The action of selecting part of an image. The Crop button on the
ScanGear CS-U main window lets you select part of a preview image and
re-preview or scan only that selected part.
Curve chart
The graph displayed in the Tone tab settings for the Auto Tone, Contrast/
Brightness, Gamma, Histogram, and Special Tone Curves features. This
graph describes the relationship between the color characteristics of the
previewed image and the available feature...

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End points
The points at each end of a preset or custom tone curve. The curve end
points cannot be deleted. If they are dragged to or past an edge, they
remain on the edge. Add points to the curve by clicking anywhere in the
curve box.
Executive
A standard U.S. paper size measuring 7.25 x 10.5 in (184.2 x 266.7 mm)
Eyedropper
A Histogram tool used to sample the Black-point, Mid-point, and White-
point areas in the previewed image. (Tone tab - Histogram)
FA U...

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Grayscale
Grayscale refers to a single-channel image made up of 256 shades of
gray, ranging from white to black, that represent all tones in an image.
Halftoning
A method of simulating intermediate tones in black-and-white images by
varying the patterns dots and lines. Halftoning is usually used for
photographs, or other images with intermediate tones, scanned in Black
and White.
Height
The Height text box contains the height of the current selection, or, if...

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Mid-point
The mid-tone portion of the image scanned as Color or Grayscale. When
you click on the image with the Mid-point eyedropper, all tones between
the black-point and white-point are adjusted in relation to the mid-point
setting.
Mid-tone
Mid-tones are the middle range of tones in an image, between
highlights and shadows. Midtones can be adjusted for color and
grayscale images with the Gamma tool.
moiré reduction
Moiré reduction can be switched on with...

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Output size
The size of the acquired image, calculated by multiplying the width and
height by the scale percentage.
Overexposed
An image that was exposed to too much light while it was being
photographed.
Paper Size
An option on the Scanner sheet that determines the initial scanning
area. Business card, Statement, B5, Executive, Letter, A4 and Full Platen
are available.
Pixel
An acronym for picture element, a pixel is the smallest element used
to create a...

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Preview image cache
When the preview image cache feature is switched on, the image in the
Preview Area from the previous session with ScanGear CS-U is saved and
displayed the next time ScanGear CS-U is launched from the parent
software application.  To switch this feature on and off, open the
Preferences sheet for your scanner and click the button for “Display
saved preview image”.
Proportion
The ratio of width to height. When you click the Keep Proportions...

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Scale
The Scale setting lets you specify an output size for the selected image as
a percent of the original width and height.
Scan button
Clicking the Scan button scans the original and sends it to the host
software application.
Scanner
An input device that scans an original with a light source, and converts
the image tones to digital information for computer applications. The
digital information can be saved as a file, or converted to a text file using
OCR...

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Test Scanner button
The Test Scanner button on the Scanner sheet starts diagnostic tests and
reports if there are any problems with the scanner.
Text Enhanced(OCR)
A feature used by ScanGear CS-U to increase the accuracy of text scans.
When Text Enhanced is selected for the Color Mode, images are scanned
as Grayscale (8 bits per pixel) and converted to Black and White (1 bit
per pixel) using Canon ImageTrust processing software.
Threshold
In a...