Many people scan materials in the Student Multimedia Design Center but few ask about resolution. Resolution values are often expressed in dots per inch (dpi). A 300 dpi resolution may produce a very readable image of a text article. Scanning a color photo or passport page at 600 dpi will create a larger file size but generally produces an image that shows fine details.
The article You Say You Want a Resolution: How Much DPI/PPI is Too Much? discusses scanning resolution issues as they relate to archiving. As the Center's scanner/copiers default to 300 dpi but may be set to 600 dpi, it's may be helpful to ask users how their scanned images will be used and help them to choose an appropriate setting. The Center will offer a workshop on Digitizing Old Formats: Photos and Video in the Fall semester that addresses these issues.
Interesting article. The experts seemed very focused on printed photos. They didn't seem to account for the fact that when a photograph is digitized, it can be viewed at any zoom level on the screen. If someone wants to study or blow up a particular fine detail of a photograph or document, the decision to scan at 600 vs. 300 DPI can be more important. Something many people don't realize is that when you view a large photograph on a computer screen, you are usually not viewing it at "actual size". The computer is using math to delete the right pixels so that you get an accurate approximation. This approximation can cause blurriness, which can be avoided by choosing "actual size" or "100%" from the view menu. The part about data stored on hard drives not being accessible in 15 years is true regardless of the resolution of the photographs.
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