Digital Scanners

High-end (technically complex and expensive) digital scanners are typically used where a professional quality image is necessary, such as in magazine publishing. These scanners often use lasers to read the original images. The image is placed in a transparent drum, which rotates past the laser. The document is scanned in a precise pattern, and is scanned in great detail (i.e., one pixel at a time). After computer processing to ensure the image will print correctly, the images are printed onto film in a process that again uses a laser.

A primary reason that digital scanners became popular beginning in the 1980s was that they created betterpublished results more cheaply. Photographs reproduced in magazines and newspapers are converted into patterns of dots, called halftones, for publication. Before digital scanners, halftones were produced using cameras. With scanners, halftones in most cases could be made more cheaply and easily. Using digital scanners also allowed for adjusting the size, sharpness and type of halftone screen to a degree not possible with cameras.

As well, because the digital images are maintained as computer files, they are much easier to store than photographic prints and negatives, and are hardier than negatives (which can be scratched or decay over time). The files can also be easily shared between computers via electronic mail. Thus, in a publishing company, each branch does not need to have its own repository of photographs. A central data bank of filed images can be useful to employees all over the globe.