Canon BJC 3000 Reference Manual page 279

Check 1
Are you using a clear image for scanning?
Blurry images are not suited for scanning. For best scanning results,
always use a clear, sharp images. (Please note that the scanned image
cannot be better than the original image.)
Check 2
Is a scanning holder unstained and undamaged?
As you use the scanning holder with the image you wish to scan, it is bound
to get dirty. Clean the scanning holder using a soft cloth that is dipped in a
weak, neutral detergent solution, and then wipe its wet surface off with a
dry, soft cloth.
If the scanning holder is scratched or damaged, replace it.
Additional scanning holders for A5-size and A4-size can be purchased
Note
optionally. Please note that the availability differs from area to area.
Check 3
Are you scanning thick paper?
For scanning, an image you use must be thinner than 0.25mm. Please
also note that the thickness including the scanning holder must be thinner
than 0.45mm.
Troubleshooting - Scanning result is unsatisfactory
Scanned image blurred or distorted
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