Flatbed scanner

Often quoted on scanner specifications to indicate the maximum tone range that the scanner can capture. A higher figure indicates that the scanner will capture more detail from the highlights to shadows. With flatbed scanners that are being used to scan prints this isn't too important because the tonal range has already been reduced in the printing process. A higher dynamic range is essential on film scanners when scanning transparencies that have a wide tonal range. Specialist films, such as Fuji Velvia, are said to have a range of around 3.7D, so the scanner needs to have at least the same dynamic range to ensure every bit of highlight and shadow detail is captured in one scan. Also see "High Dynamic Range"