Canon PIXMA MG2525 All-in-One Inkjet Printer (Black) - Manual (Page 162)

Slow Scanning Speed
Check 1: To view the image on a monitor, set the output
resolution to around 150 dpi. To print, set it to around 300 dpi.
Resolution
Check 2: Set Fading Correction, Grain Correction, etc. to None.
Refer to " Image Corrections and Color Adjustments " for details.
Check 3: In IJ Scan Utility, deselect the Correct slanted text
document / Detect the orientation of text document and rotate
image checkbox and scan again.
Settings (Document Scan) Dialog
Settings (Custom Scan) Dialog
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