Scanning Fundamentals
After placing the image face down, aligned straight on the scanner bed, ensure you select the correct document type to achieve the highest quality. Even if you’re restoring old black-and-white photos, it’s worth setting the Document Type to Color Photo when scanning to make sure maximum detail is retained. The same applies to black-and-white slides or negatives which can later be converted into greyscale using Photoshop’s Mode menu.
Resolution is the key term when it comes to scanning. It relates to the number of pixels or dots sampled from the image. Resolution is measured in dots per inch (dpi) and the higher the setting, the greater the quality of your image. A higher setting also means you’ll be able to enlarge your image later. If you’re scanning damaged photos, resolution should be set no lower than 300dpi and they should be saved using the highest quality setting.
It’s also useful to hit Preview first to see a quick, low-res overview of your image on-screen before you commit it to scan, incase of problems – eg being placed at an angle on the scan bed.
Excerpts from article in Photoshop Creative Issue fifteen.
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