These PhotoCD images can be displayed on a television set or can be used in a desktop page layout and separated to film. A complex technology, the achievable quality depends on a talented computer operator with knowledge of color prepress techniques. That in hand, PhotoCD can achieve above average quality color separations for a low unit cost. Pixel The smallest building block within a scanned line-art or photographic image. A pixel is the small square picture element that is filled with a color, or black or white.
Pixels come in various sizes and their size is expressed in terms of resolution.
PMT Photo Multiplier Tube. A light sensing element used in high quality drum scanners. It is said that scanners using PMT technology create the highest quality scans. PPI Pixels Per Inch. An expression of resolution of a scanned image.