Middle gray
Encyclopedia
In photography
, painting
, and other visual arts, middle gray or middle grey is a tone that is perceptually about half way between black and white on a lightness
scale; in photography, it is typically defined as 18% reflectance in visible light.
Middle gray is the universal measurement standard in photographic cameras. To calibrate light meters, whether in a camera or hand held, the 18% gray card
was conceived. It is assumed that the measurement taken by a meter gives the exposure for a shot so that some of the light reflected by the object measured is equivalent to middle gray. However, many note that modern cameras generally treat 12-13% gray as "middle gray".
In the sRGB color space, middle gray is equivalent to 46.6% brightness. In 24-bit color, this is rounded to RGB value (119,119,119) or #777777.
of Ansel Adams
, middle gray is known as "Zone V" in the scale of 11 zones from Zone 0 (black) to Zone X (white).
As early as 1903, middle gray was defined as the geometric mean
intensity between a white and a black intensity that are in a ratio of 60:1. That is equivalent to 12.9% of the white intensity.
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...
, painting
Painting
Painting is the practice of applying paint, pigment, color or other medium to a surface . The application of the medium is commonly applied to the base with a brush but other objects can be used. In art, the term painting describes both the act and the result of the action. However, painting is...
, and other visual arts, middle gray or middle grey is a tone that is perceptually about half way between black and white on a lightness
Lightness (color)
Lightness is a property of a color, or a dimension of a color space, that is defined in a way to reflect the subjective brightness perception of a color for humans along a lightness–darkness axis. A color's lightness also corresponds to its amplitude.Various color models have an explicit term for...
scale; in photography, it is typically defined as 18% reflectance in visible light.
Middle gray is the universal measurement standard in photographic cameras. To calibrate light meters, whether in a camera or hand held, the 18% gray card
Gray card
A gray card is a middle gray reference, typically used together with a reflective light meter, as a way to produce consistent image exposure and/or color in film and photography....
was conceived. It is assumed that the measurement taken by a meter gives the exposure for a shot so that some of the light reflected by the object measured is equivalent to middle gray. However, many note that modern cameras generally treat 12-13% gray as "middle gray".
In the sRGB color space, middle gray is equivalent to 46.6% brightness. In 24-bit color, this is rounded to RGB value (119,119,119) or #777777.
History
In the Zone SystemZone system
The Zone System is a photographic technique for determining optimal film exposure and development, formulated by Ansel Adams and Fred Archer. Adams described how the Zone System was developed: "I take this opportunity to restate that the Zone System is not an invention of mine; it is a codification...
of Ansel Adams
Ansel Adams
Ansel Easton Adams was an American photographer and environmentalist, best known for his black-and-white photographs of the American West, especially in Yosemite National Park....
, middle gray is known as "Zone V" in the scale of 11 zones from Zone 0 (black) to Zone X (white).
As early as 1903, middle gray was defined as the geometric mean
Geometric mean
The geometric mean, in mathematics, is a type of mean or average, which indicates the central tendency or typical value of a set of numbers. It is similar to the arithmetic mean, except that the numbers are multiplied and then the nth root of the resulting product is taken.For instance, the...
intensity between a white and a black intensity that are in a ratio of 60:1. That is equivalent to 12.9% of the white intensity.