Canon scanner CanoScan D660U User Manual

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Pre-Scan Checklist
Perform the checks on this short list before you begin troubleshooting
specific problems.
•Make sure that the ScanGear CS-U software was installed
successfully.
•Confirm that the cables between your computer and scanner are
connected securely.
•Before scanning or previewing, check that the data source has
been selected. If your scanner does not appear as an option when
you select a TWAIN source to scan from your imaging software,
you have to install ScanGear CS-U again. (
p.12) 
						

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How to Avoid Problems
Here is some general advice on avoiding problems in your scanning jobs:
•Start with the best possible original image to scan.
•Select only the part of the image you want to scan. Preview the
image and select it with the Crop and Auto Crop buttons. Not only
does a more precise selection save file space, but your image
quality will be much higher.
•Check the output file size before beginning the scan. Make sure
you have enough room if you are scanning files that require a large
amount of disk space.
•Match your Color Mode to the output purpose. If you are scanning
text, use the Text Enhanced mode. If you are scanning line art, use
the Black and White setting, and so on.
•Match your scan resolution to the type of file you need. If you are
scanning images for use as .GIF or .JPG files on the Web, you do
not have to scan at 600 dpi. Although it is recommended that you
scan at a higher resolution than you need for high-quality color
images, you should balance that factor against your planned use
for the image.
•Take advantage of the Tone sheet features to enhance your images.
(
p.41)
•Try to use TrueColor mode on your monitor so you can view your
preview image as accurately as possible. 
						

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•If you are using OCR software, scan in Text Enhanced at 300 dpi or
higher.
•Take advantage of the preview feature and preview as much as you
want before scanning. 
						

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Troubleshooting Checklist
The scanner diagnostics test fails.
Problem:The Scanner Diagnostics test, started with the Test Scanner
button on the Scanner sheet, returns a Test Failed
message.
Cause:The scanning unit may not be in its home position.
Solution:Close the ScanGear CS-U window if it is open. Try turning
the scanner off and back on again by unplugging and
plugging in the USB cable. Then restart your computer.
Colors not what you expect.
Problem:The colors in the preview image appear different from the
colors in the original image.
Cause1:The scanned colors need to be adjusted.
Solution:Make sure the Auto Tone button is selected. If further
adjustments are necessary, use the Tone sheet buttons.
Cause2:The calibration slot on the film guide is obstructed.
Solution:Clear the item blocking the calibration slot.
The preview image of a photograph appears blurred but the
scanned image of the same photograph appears sharp.
Problem:When zooming in on a photograph in the Preview area,
the enlarged image appears blurred.
Cause:The preview scan uses a lower resolution than the final
scan. If you zoom in on a preview image so it is enlarged,
the image will not maintain its resolution in the same way
as the final scanned image.
Solution:Select a magnified area and preview the image again. The
scan should display a sharper image. 
						

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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.
Cause1:The scanner may not be connected correctly.
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.
Cause2:You may have chosen the wrong scanner source in your
software application.
Solution:Make sure you selected the correct scanner in the parent
software application.  For details, see your software
application documentation for instructions.
Cause3:The scanner configuration file may have been changed.
Solution:Uninstall ScanGear CS-U (
p.16) then reinstall ScanGear
CS-U (
p.13).
Cant scan with the film adapter unit.
Problem:Cant scan with the film adapter unit.
Cause:Film adapter units connector cable is detached.
Solution:Attach the film adapter units connector cable correctly. 
						

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Scanning is too slow.
Problem:The scanner is taking an unusually long time to print or
scan.
Cause1: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.
Cause 2:DMA option for computer’s hard disk drive is not turned
on.
Solution: Windows 98: Turn on the DMA option in the System
Properties dialog as described below.
Right-click the [My Computer] icon on the Windows
desktop, select [Properties] from the pop-up menu and
click the [Device Manager] tab in the System Properties
dialog. In the [Disk Drives] category, select the appropriate
hard disk and click the [Properties] button on the Device
Manager tab. Click the [Settings] tab and place a check in
the [DMA] option. Restart the computer. (Please consult
the manufacturer of your computer for confirmation that
the DMA function is supported.)
Windows 2000: Turn on the DMA option. The procedures
are similar to those for Windows 98 with a few variations. 
						

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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.
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.78)
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.