A very good book that covers everything about scanning is "Real World
Scanning and Halftones" by David Blatner and Steve Roth, 1993 Peachpit
Press, Inc., 2414 Sixth Street, Berkeley CA 94710; Phone 510/548-4393;
Fax 510/548-5991; ISBN 1-56609-093-8. It really is excellent and
should answer your questions.
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