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When I scan a picture from a magazine or book, the image appears all blotchy.

The blotchy appearance is almost certainly what is known as a Moiré pattern and is caused by interference between the patterns of tiny dots comprising the printed image and the chosen scanning resolution.  This is a simple fact of imaging printed media digitally, and does not indicate a fault with the equipment. Scanning at a different resolution will usually solve the problem.

You will almost certainly find that a scanning resolution of only 96dpi will produce a perfectly acceptable scan for onscreen display, and will avoid the problem of Moiré interference.  If not, try different scanning resolutions, but remember that the higher the resolution you use, the larger the image will be and the more memory it will use.

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This is question number 1092, which appears in the following categories:

Created by Andy Clews on 12 May 2004 and last updated by Claire Craig on 23 June 2015