Color printing yellow (minus-blue) overprinted by magenta (minus green) yields red. Where all three inks may overlap, almost all incident light is absorbed or subtracted, yielding near black, but in practical terms it is better and cheaper to use a separate black ink instead of combining three colored inks. The secondary or subtractive colors cyan, magenta and yellow may be considered "primary" by printers and watercolorists (whose basic inks and paints are transparent). Two graphic techniques are required to prepare images for four-color printing. In the "pre-press" stage, original images are translated into forms that can be used on a printing press,
Combination printing would be able to combine the two negatives by blending them together. Photographers such as William Frederick Lake Price and Oscar Rejlander are famous for using combination printing. Starting as early as the mid-19th century, new methods such as the combination printing, began to change the way people looked at different photographic techniques. Controversy broke out in the photographic community about the use of combination printing. Photographs originally had been regarded as truth and it was perceived that the camera never lied. However, with the newfound ability to manipulate the final product, the notion that photographs depicted "truth" was soon