Primary color overlaid partially absorbing materials on a reflecting or transparent surface. Each layer partially absorbs some wavelengths of light from the illumination spectrum while letting others pass through multiplicatively, resulting in a colored appearance. Overlapping layers of ink in printing mix subtractively over reflecting white paper in this way to generate photorealistic color images. The typical number of inks in such a printing process ranges from 3 to 6 (e.g., CMYK process, Pantone hexachrome). In general, using fewer inks as primaries results in more economical printing but using more may result in better color reproduction. Cyan, magenta, and yellow are good
Combination printing Combination printing Combination printing is the photographic technique of using the negatives of two or more images in conjunction with one another to create a single image. Similar to dual-negative landscape photography, combination printing was technically much more complex. The concept of combination printing stemmed from the desire to create more of a fine art within photography and often more idealized images. Combination printing was popular in the mid-19th century due to the limitations of the negative's light sensitivity and camera technology. For example, the long exposures required at the time to create an image would properly expose the main