Monochrome

Monochrome describes paintings, drawings, design, or photographs in one color or values of one color. A monochromatic object or image reflects colors in shades of limited colors or hues. Images using only shades of grey (with or without black or white) are called grayscale or black-and-white. However, scientifically speaking, monochromatic light refers to visible light of a narrow band of wavelengths (see spectral color).

For an image, the term monochrome is usually taken to mean the same as black and white or, more likely, grayscale, but may also be used to refer to other combinations containing only tones of a single color, such as green-and-white or green-and-black. It may also refer to sepia displaying tones from light tan to dark brown or cyanotype (“blueprint”) images, and early photographic methods such as daguerreotypes, ambrotypes, and tintypes, each of which may be used to produce a monochromatic image.

In computing, monochrome has two meanings:

A monochrome computer display is able to display only a single color, often green, amber, red or white, and often also shades of that color.

In film photography, monochrome is typically the use of black-and-white film. Originally, all photography was done in monochrome. Although color photography was possible even in the late 1800s, easily-used color films, such as Kodachrome, were not available until the mid-1930s.

In digital photography, monochrome is the capture of only shades of black by the sensor, or by post-processing a color image to present only the perceived brightness by combining the values of multiple channels (usually red, blue, and green). The weighting of individual channels may be selected to achieve a desired artistic effect; if only the red channel is selected by the weighting then the effect will be similar to that of using a red filter on panchromatic film. If the red channel is eliminated and the green and blue combined then the effect will be similar to that of orthochromatic film or the use of a cyan filter on panchromatic film. The selection of weighting thus allows a wide range of artistic expression in the final monochromatic image.

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Wikipedia