Color printing digital printing methods do not have the restriction of a single color space that traditional CMYK processes do. Many presses can print from files that were ripped with images using either RGB or CMYK modes. The color reproduction abilities of a particular color space can vary; the process of obtaining accurate colors within a color model is called color matching. Inks used in color printing presses are semi-transparent and can be printed on top of each other to produce different hues. For example, green results from printing yellow and cyan inks on top of each other. However, a printing press
Early American editions of The Hobbit 14th impressions come in a variety of colors. Generally all the books from one printing are bound in the same color, but exceptions may have been found, perhaps when bindings intended for one printing were left over and found use at the beginning of the next printing. Hence the color of the covers cannot conclusively identify a book. The 6th impression's blue-green is medium light and distinctly blue. The 7th impression's khaki binding, on the other hand, shows no hint of blue or green. Its color is considerably darker than the 10th through 12th impressions. The rust color of the