These scanners may be faster to use, but the flat bed scanner is much less likely to damage the surface of photographs and take off pieces of old brittle paper. Two parameters that determine the quality of a scanner are resolution and speed. Speed is less of a concern if you only scan an occasional photo, but if you have a stack of photographs to do, a slow scanning rate will keep you waiting, and be a cause of frustration. Speed is often omitted when scanner features are mentioned, and it may take some digging to find information about scanning speed. The scanning rate is measured in dots per minute, although a more common way to describe speed is to mention a time to scan a standard size picture.
Resolution is measured in dots per inch.
Specifications are usually given for an optical resolution and for a pixel resolution of the scanned data which are usually different. Higher resolution in the scanner produces finer detail in the scanned image, thus giving a more accurate image of the original picture. Most scanners sold now have a resolution of 600 dots per inch, and the more expensive models will have 1200 dpi and higher. There many choices are available today if you want to buy a scanner. The software for scanning pictures is normally included with the scanner.