Canon scanner CanoScan N656U User Manual

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The colors differ between the Preview and the Print
Problem:When printing the image, its color differ from the one in
the Preview area.
Cause1:The toner of the printer is going short.
Solution:Confirm the toner of the printer.
Cause2:Canon ColorGear Color Matching may have not been
selected when it was necessary.
Solution:Check that Canon ColorGear Color Matching is selected
on the Preferences sheet.
Cause3:The settings of the printer driver, such as color balance or
Gamma, do not match to the printer.
Solution1:Adjust the color balance in the printer driver manually.
Solution2:Change the Gamma value setting of the printer driver.
The software application cannot find the scanner.
Problem:When trying to scan, an error message says the scanner
cannot be found.
Cause:Windows may not recognize your scanner.
Solution:Make sure the scanner is connected to your computer
before you turned on the computer and started Windows.
If not, connect the scanner.  Then restart your computer. If
this does not correct the problem, consult the scanner user
manual for additional information about how to properly
set up your scanner.
Some buttons are grayed-out.
Problem:Buttons in the Toolbar are grayed-out and not available.
Cause:Some functions are not available until an image has been
previewed.
Solution:Preview an image. 
						

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ScanGear CS-U does not launch.
Problem:ScanGear CS-U does not launch, the screen freezes, or
another software application launches.
Cause:The scanner may not be connected correctly, or you may
have chosen the wrong scanner source in your software
application. The scanner configuration file may have been
changed.
Solution:Make sure the scanner is properly connected to your
computer before you turn on the computer and start
Windows. If not, connect the scanner.  Then restart your
computer.
Make sure you selected the correct scanner in the parent
software application.  For details, see your software
application documentation for instructions.
If neither of those steps solve the problem, uninstall
ScanGear CS-U (
p.16) then reinstall ScanGear CS-U
(
p.13). 
						

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Scanning is too slow.
Problem:The scanner is taking an unusually long time to print or
scan.
Cause:The selected output resolution of the image may be too
high for the resolution of your printer, or your computer
may be low on memory.
Solution:Before scanning the image, make sure you have set the
Scan Resolution on the Main tab to not exceed the
resolution of your printer.  Also check to see if there is
enough memory available in your computer.  Before
scanning, quit other applications that are not in use.
Parts of images are missing or not aligned.
Problem:Some characters are missing from the image in the Preview
Area, or the image is not aligned in the Preview Area.
Cause:The page has been placed on the scanner improperly.
Solution:Check the scanner and place the original correctly to adjust
the image.
Image is too light or too dark compared to the original.
Problem:Scanned or printed image is much lighter or darker than
the original.
Cause:Image and color adjustments may not have been set
properly.
Solution:The best solution is to scan the image using all default
settings again.  Then make imaging and color adjustments
as necessary. 
						

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The preview image is too small on the monitor
Problem:The image in the Preview Area is very small, and cannot be
viewed in the Preview Area for adjustment.
Cause:If you have a high-resolution setting on your monitor, the
ScanGear CS-U window is smaller than if you had a lower-
resolution setting.
Solution:Drag the Window Resize Corner (
p.26) on the lower
right of the ScanGear CS-U window to enlarge the entire
window or lower your monitors resolution with the
Control Panel. 
						

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Glossary 
						

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Acquired Images
Images sent from your scanner software to the host graphics application.
Auto Crop
After you select an area of the screen by clicking the Crop button and
dragging a rectangle around the object or text you want to crop, click
the Auto Crop button to size the rectangle exactly to the size of the
object or block of text enclosed in the rectangle.
Auto Tone Adjustment
Automatic analysis and adjustment of the image using Contrast/
Brightness and Gamma settings.
Automatic Preview
When the automatic preview feature is switched on, the original on the
scanner is pre-scanned immediately as 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
“Automatically execute a preview”. (
p.74)
Bits and Bit Depth
A bit (Binary digit) is the smallest possible unit of information on a
computer; it represents yes or no; on or off; 1 or 0. Bit Depth is used to
describe the complexity of a graphic image.
One-bit, or bi-level, images are black and white. This is the Black and
White setting in ScanGear CS-U. Eight-bit grayscale uses 256 shades of
gray to accurately represent most black and white photographs or gray
interpretations of color images. This is the
Grayscale setting in ScanGear CS-U. Twenty-four-bit color, also called
True Color, uses three eight-bit channels, one channel each for Red,
Green and Blue, to create up to 16.7 million colors. This is the Color
setting in ScanGear CS-U. 
						

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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 refers to the intensity of tones.
Calibration
Calibration refers to the adjustment of color processing for input and
output devices on a computer, so that the colors match throughout the
process. For example, calibration ensures that the color image scanned
on a scanner matches the original image when it is displayed on the
computer monitor, as well as printed on a color printer.
Canon ColorGear Color Matching
Canons process of matching the color profile of the input device
(scanner) with the color profile of the output device (monitor), to yield
the most accurate color image.
Canon ImageTrust
Canons process of converting grayscale image (8 bits per pixel) to a
black and white image (1 bit per pixel) to yield a more effective scan for
optical character recognition (OCR) applications.
Channel
See Color Channels. 
						

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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
The range of colors your scanner can see may not match the range of
colors your video monitor can produce. Color matching lets your system
display colors so that the color on your monitor and printer matches the
colors scanned. See also Canon ColorGear Color Matching.
Color Mode
The type of scan used to scan an image, differentiated by the number of
bits per pixel. ScanGear CS-U has the following Color Modes:
Color(Photo), Color (Documents, Charts), Grayscale, Text
Enhanced(OCR), and Black and White.
Contrast
Contrast refers to the difference between the lightest light and the
darkest dark in the image. A low contrast value indicates that the
difference between dark shades and light shades is not very great. A
high value indicates a great difference between dark and light shades.
While brightness refers to the intensity of tones in an image, contrast
refers to the range and number of tones in an image. 
						

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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 settings.
Curve file
A file containing Special Tone Curve settings. (Tone tab-Special Tone
Curves)
Custom curves
A user-defined Special Tone Curve that may be saved in a file. (Tone tab-
Special Tone Curves)
Default
The preset factory settings on hardware or software.
Digitizing
The process of converting an image into computer-usable (digital)
information that can be saved as a file, printed, faxed, or otherwise
manipulated on your computer.
dpi
The abbreviation for dots per inch. The resolution of a monitor or printer
is measured in how many dots per horizontal inch it can display or print.
See also Pixel, Optical resolution, Resolution. 
						

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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 U.S. standard 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)
Full Platen
The maximum scanning area on the scanners document glass,
216 x 297 mm (width of U.S. Letter and length of A4 paper sizes).
Gamma Curve
The Gamma Curve lets you change the midtones of colors to increase
the contrast between colors, and enhance the overall image. When you
increase the Gamma value, light colors are made lighter, and dark colors
are made darker. The graphed curve represents the relationship between
input and output values for the midtones of the preview image.