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Cyan

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Cyan (#00FFFF)
#00FFFF

Cyan (from Greek κυανός, meaning "blue") may be used as the name of any of a number of a range of colors in the blue/green part of the spectrum. In reference to the visible spectrum cyan is used to refer to the color obtained by mixing equal amounts of green and blue light or the removal of red from white light. As such, cyan is the complement of red in RGB and CMYK color systems: cyan pigments absorb red light.

Cyan is also called aqua or blue-green, and was previously known as "cyan blue".[1]

Some shades of color close to cyan in the cyan color range are baby blue, turquoise and aquamarine.

In this 1889 dictionary, cyan-blue is defined as the blue-green color corresponding to wavelengths from 487 to 505 nm, corresponding to what is today called cyan.

Electric cyan vs. process cyan

Electric cyan (web color aqua)

Cyan (additive secondary)
 
About these coordinates     Color coordinates
Hex triplet#00FFFF
sRGBB (r, g, b)(0, 255, 255)
HSV (h, s, v)(180°, 100%, 100%)
CIELChuv (L, C, h)(91, 72, 192°)
SourceX11
B: Normalized to [0–255] (byte)

The vivid cyan that is seen on an electronic display device (shown at right) is also referred to as electric cyan to distinguish it from the less vivid turquoise-like process cyan used in CMYK color printing (shown below). (Note: while the color is defined by definite RGB values, the display of the color will vary depending on the absolute color space used and the nature of the physical display device, e.g. computer monitor, and if this page is printed it is likely that the color shown will be far from representative.)

The web color aqua is an alias for electric cyan, i.e., it is exactly the same color.

To reproduce electric cyan in inks, it is necessary to add some white ink to the printer's cyan below, so when it is reproduced in printing, it is not a primary subtractive color. It is called aqua (a name in use since 1598) because it is a color commonly associated with water, such as the appearance of the water at a tropical beach.[2]

Process cyan (pigment cyan) (printer's cyan)

Cyan (subtractive primary)
 
About these coordinates     Color coordinates
Hex triplet#00B7EB
sRGBB (r, g, b)(0, 183, 235)
HSV (h, s, v)(193°, 100%, 92%)
CIELChuv (L, C, h)(69, 74, 229°)
Source[citation needed][3] CMYK
B: Normalized to [0–255] (byte)

Cyan is also one of the common inks used in four-color printing, along with magenta, yellow, and black; this set of colors is referred to as CMYK.

While both the additive secondary and the subtractive primary are called cyan, they can be substantially different from one another. Cyan printing ink can be more saturated or less saturated than the RGB secondary cyan, depending on what RGB color space and ink are considered.

Process cyan is not an RGB color, and there is no fixed conversion from CMYK primaries to RGB. Different formulations are used for printer's ink, so there can be variations in the printed color that is pure cyan ink. A typical formulation of process cyan is shown in the color box at right. The source of the color shown at right is the color cyan that is shown in the diagram located at the bottom of the following website offering tintbooks for CMYK printing:[4].

Variations of Cyan

Light Sea Green

Light Sea Green
 
About these coordinates     Color coordinates
Hex triplet#20B2AA
sRGBB (r, g, b)(32, 178, 170)
HSV (h, s, v)(177°, 82%, 70%)
CIELChuv (L, C, h)(66, 50, 184°)
SourceX11
B: Normalized to [0–255] (byte)

At right is displayed the web color light sea green.

Dark Cyan

Dark Cyan
 
About these coordinates     Color coordinates
Hex triplet#008B8B
sRGBB (r, g, b)(0, 139, 139)
HSV (h, s, v)(180°, 100%, 55%)
CIELChuv (L, C, h)(52, 41, 192°)
SourceX11
B: Normalized to [0–255] (byte)

At right is displayed the web color dark cyan.

Spectral reflectance curve of cyan

File:Cyan1.png
spectral reflectance curve


Cyan in nature

Cyan in human culture

  • Cyan colored tiles are often used to pave swimming pools to make the water within them seem more inviting to swim in, by making the cyan color of their water seem more intensely colored. Water in swimming pool is colored a bright tint of cyan anyway because chlorine bleach, which is cyan, is added to water in swimming pools for disinfection.
  • Cyanosis is an abnormal blueness of the skin, usually a sign of poor oxygen intake. IE- the patient is "cyanotic"
  • Cyan is the name of a character in the Norwegian comic strip Nemi.

References

  1. ^ J. Arthur H. Hatt (1908). The Colorist: Designed to Correct the Commonly Held Theory that Red, Yellow, and Blue are the Primary Colors and to Supply the Much Needed Easy Method of Determining Color Harmony. D. Van Nostrand Company.
  2. ^ Maerz and Paul The Dictionary of Color 1930 (see under Aqua in Index, Page 189)
  3. ^ http://www.tintbook.com/
  4. ^ http://www.tintbook.com/
  5. ^ Mike Ware (1999). Cyanotype: the history, science and art of photographic printing in Prussian blue. NMSI Trading Ltd. ISBN 1900747073.

See also