The Color Printer/Definitions
Definitions of Terms.
Primary Colors—Red, Yellow, and Blue are called the primary colors, because they are the first or original colors from which all others can be made.
Secondary Colors—Orange, Green, and Violet are called the secondary colors, because they are of the second formation, each color being produced by a mixture of two of the primary colors. The Orange, from red and yellow; the Green, from yellow and blue; and the Violet, from blue and red.
Tertiary Colors—Russet, Olive, and Citron are called the tertiary colors, because they are of the third formation, each color being produced by a mixture of two of the secondary colors. The Russet, from orange and violet; the Olive from violet and green; and the Citron, from green and orange.
A Full Color is a color in its purest state—one which has not been changed by the addition of white or black. The primaries, secondaries, and their various hues are full colors. See Plate 32.
A Hue is a primary or secondary color slightly changed by the addition of a neighboring color, For example, a green-blue is a hue of blue; a blue-green is a hue of green. See Plate 32.
A Tint is a very light or pale color, produced by adding a small quantity of color to a greater quantity of white. For example see Plates 19, 20, and 21.
A Shade is a dark or broken color, produced by the mixture of a full color with gray or black. For example see Figs. 31 to 36, and many others throughout this work.
A Half-tone is a color reduced to about one-half its original strength by the addition of white. For example see Plates 17 and 18.
The Light Tones of a color are the various degrees of color produced by the mixture of a full color with white. For example, Fig. 133 on Plate 17, and Fig. 149 on Plate 19, are two of the light tones of red.
The Dark Tones of a color are the various degrees of color produced by the mixture of a full color with black. For example, Figs. 35 and 36 on Plate 4, are two of the dark tones of red.
By Color Scale is meant all of the different tones of a color, ranging from the darkest shade to the full color, and from the full color to the lightest tint.
A Warm Color is any color in which red or yellow predominates.
A Cold Color is any color in which blue predominates.
Complementary Color.—Any color is complementary to another, when by a mixture of the two, prismatically, white light is produced.
Spectral Color.—A spectral color is the tint which is seen upon a white surface, after looking upon a colored object for some minutes. The tint will in every case be exactly complementary to the color looked upon.
Prismatic Colors.—The different colors produced by the refraction of the sunlight as it passes through a triangular piece of clear glass called a prism.
The Retina is a delicate membrane inside of the eye, upon which is projected by the crystalline lens, the image of any object coming before it. In operation the eye is similar to that of the photographic camera. It is said that the retina is composed of three sets of fine nerve-fibres intermixed; one set being sensitive to the action of red, another to yellow, and the other to blue. These nerve-fibres unite in the back part of the eye, forming what is known as the optic nerve, which connects the eye with the brain.