I am adding the following info from another topic, so that it is all in the same place.Here are some examples of some bad scans and some tips on improving them from Rocket2600.
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Originally posted by Rocket2600
We are getting in alot of scans that are properly cropped but have alot of scanline patterns.
Look at these 2 examples:
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If you are scanning and have covers turn out like this, please try rescanning at a higher DPI. Most times this will solve this issue. If you are "borrowing" the scans from another source, then just skip these poor looking scans. We can find better cover scans than this.

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Originally posted by Rocket2600
Also, scanning with the comic in the bag is a no-no. V

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Originally posted by Shadow
What he said...
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But on the "bag" issue...if there is graphics on the bag...and it makes a difference on whether it's "#1" or "#1A"...like with some of the Milestone #1's...take some time and get a good scan on it...
It's not that tough to smooth out the bag and make a proper scan...8D
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Originally posted by Rocket2600
Ah yes, I have done this with a few scans also.
Some that come bagged with a card. Example:
(bagged and opened)
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Just try to smooth out the bag while scanning.
It will help reduce any light glares from the scanner's bulb.