How to Choose a Photo Scanner
- 1). Determine what you want to scan. Do you need to scan small photos; documents that are 8.5 x 11" or 8.5 x 14"; pages from books; 3-D objects; or slides and negatives? Flatbed scanners can handle all of the above and, with the use of a transparency adapter, can scan 35 mm negatives and 35 mm slides with good results.
If, however, you want to convert shoe boxes filled with old slides and negatives to digital format, get a dedicated film scanner. Those are more expensive but are designed to convert large volumes of older media to high-quality digital files. - 2). Determine the resolution needed, based on how you will use the scan. Scanners are advertised as being capable of scanning in dpi, or dots per inch. The more dots of information per inch a scanner detects, the more resolution it has. A low amount of information will result in blocky, murky images.
What you are going to do with the final scan will determine how high a resolution scanner you need. For Web or computer display only, something that scans at 72 dpi will be adequate. But if you want to scan a 4 x 6" photo and print it at the same size, you need to scan at 300 dpi; to blow it up to 8 x 12" requires at least 600 dpi. A general rule of thumb is to double the dpi with every doubling in size. Using the same example, a poster-size photo (16 x 24") would need the scanning dpi to be 1200 to reproduce. - 3). Choose the brand of scanner. Canon, Nikon, Epson and HP---to name a few major companies---all produce high-quality, affordable, reliable scanners. Off-name brands, too, can provide what you need, often at lower prices. Check consumer reviews and watch demonstrations at computer stores before making a decision on what brand to buy.
- 4). Decide what other features you need in a scanner. Does the software need to allow for red-eye removal, dust removal, or color adjustments? Should the scanner have document holders for scanning large quantities of papers or slide carousels for scanning large volumes of slides? For usability issues, consider how easy it is to use and how long it takes to scan one image. Also, color-bit depth is another spec to consider if you want to enlarge prints or if you will be scanning negatives or slides. The greater the color-bit depth, the better the final image because the bit depth determines gradations of shading; 24-bit (8 bits per color channel) is basic, 48-bit (16 bits per channel) is better.
- 5). Determine how much you want to spend. Scanners can cost from as little as $25 up to several thousand bucks. Again, determine your requirements and wants. Casual or home users can spend $100 and get a good-quality scanner that will suit their needs. Professional photographers or printing companies may opt for higher-end scanners with top-of-the-line optics and additional features.
- 6). Assess the size of the scanner and what type of computer you will use with it. If you have a limited workspace or work out of your car, you may need a scanner that is no larger than a notebook, one that is light and easy to store and carry. A small size like this will limit the size of the originals you will be scanning, so carefully determine your needs.
Most of today's photo scanners connect to a computer using a USB interface, which is compatible with both Windows and Macintosh operating systems. Older models or used scanners can be found for sale (on sites such as eBay) but be aware that some will have a SCSI connection, a now defunct connection mode.
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