Canon 3749B002 On-Screen Manual page 632

Scanning takes longer than usual when you enable Descreen.
Reduce Show-through
Select this checkbox to sharpen text in a document or reduce show-through in newspapers.
Note
Select this checkbox when Document Type is text document and show-through is apparent in the
scanned image.
Unsharp Mask
Select this checkbox to emphasize the outline of the subjects and sharpen the image.
Remove gutter shadow
Select this checkbox to correct shadows that appear between pages when scanning open booklets.
Important
You cannot select this checkbox when Document Size is Auto Detect, Auto Detect (Multiple
Documents) or Stitch Assist.
Align the document correctly with the alignment mark on the Platen.
Note
Use ScanGear's Advanced Mode tab to correct gutter shadows when scanning non-standard size
documents or when custom cropping frames are set.
For details, see Gutter Shadow Correction in "
Correct slanted document
Select this checkbox to detect the scanned text and correct the angle (within -0.1 to -10 degrees or +0.1
to +10 degrees) of the document.
Important
You cannot select this checkbox when Document Size is Stitch Assist.
The inclination of the following types of documents may not be corrected, as the text cannot be
detected correctly.
- Documents in which the text lines are inclined more than 10 degrees or the angles vary by line
- Documents containing both vertical and horizontal text
- Documents with extremely large or small fonts
- Documents with small amount of text
- Documents containing figures/images or hand-written text
- Documents containing both vertical and horizontal lines (tables)
Note
Scanning takes longer than usual when you enable Correct slanted document.
Enable Auto Photo Fix (When scanning with Auto Scan using the Operation Panel)
Select this checkbox to analyze the photo image and apply suitable corrections automatically.
This function is available when Auto or JPEG/Exif is selected for Save as type in Save Settings on the
Scanner Button Settings tab of the Preferences dialog box.
Important
When Save as type is Auto, the base color tone of the following types of documents may change
from the source since they are corrected as photos. In that case, deselect the checkbox and scan.
- Postcards and business cards
Text documents may not be scanned correctly since they may be corrected as photos depending
on how you place the document. In that case, deselect the checkbox and scan.
Note
If you select a format other than JPEG/Exif for Save as type and then select this checkbox, a
message appears and Save as type will be set to Auto.
Detect the orientation of text documents and rotate images
Image Settings " (ScanGear's Advanced Mode tab).