This site aspires to be a collection of high-quality scans. In the past, a few people have sent us scans that
were of very low quality, and we had to decide between hurting someone's feelings, or compromising our quality
standard. To make sure that your work won't be in vain, please try to keep these guidelines in mind:
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Use a scanning resolution of at least 150 dpi. Since most scans require quality-degrading postprocessing
steps such as rotation (for proper alignment), you may want to work with 200 dpi or higher and later resample
your scans accordingly. Use a software with a good (bicubic) resampling algorithm such as Photoshop. Moiré patterns
in the final product are unacceptable.
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You can increase the quality of your scans by using unsharp masking and contrast enhancement.
Don't overdo it, though.
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Encode the scans in jpeg format, but don't set the compression too high. Up to 200k filesize for a scan of a
single page is acceptable. For oversize objects such as maps, scans can be much bigger.
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Make sure the scans are properly aligned. If they are not, we have to do it ourselves, which requires an
additional jpeg re-encoding step that degrades quality.
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When scanning oversize objects such as maps (assuming you don't have an A-3 scanner) you have two options:
either you invest the time to piece the parts together (which, when properly done, is extremely time-consuming), or
you make provisions that allow us to do it. In the latter case, make sure there is some overlap between the pieces, use at least 200 dpi,
and be extra careful to rotate the pieces into precise alignment.
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Please generate thumbnails of height 200 pixels for every picture and adhere to the naming
convention {full-size-file}-th.jpg.
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