Cyan

Cyan (IPA: /saɪæn/; from Greek κυανoῦς / kyanous, 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, teal, 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)
— Color coordinates —
Hex triplet		#00FFFF
RGBB	(r, g, b)	(0, 255, 255)
HSV	(h, s, v)	(180°, 100%, 100%)
Source		X11
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)
— Color coordinates —
Hex triplet		#00B7EB
RGBB	(r, g, b)	(0, 180, 247)
HSV	(h, s, v)	(180°, 100%, 97[3]%)
Source		CMYK[4]
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 Web site offering tint books for CMYK printing: http://www.tintbook.com/

Variations of cyan

Light sea green

Light Sea Green
— Color coordinates —
Hex triplet		#20B2AA
RGBB	(r, g, b)	(32, 178, 170)
HSV	(h, s, v)	(175°, 40%, 75%)
Source		X11
B: Normalized to [0–255] (byte)

Displayed at right is the web color light sea green.

Dark cyan

Dark Cyan
— Color coordinates —
Hex triplet		#008B8B
RGBB	(r, g, b)	(0, 139, 139)
HSV	(h, s, v)	(180°, 24%, 100%)
Source		X11
B: Normalized to [0–255] (byte)

Displayed at the right is the web color dark cyan.

Cyan spectral reflectance curve

Cyan spectral reflectance

Cyan in nature

• Pure water is nearly colorless. However, it does absorb slightly more red light than blue, giving large volumes of water a bluish tint; increased scattering of blue light due to fine particles in the water shifts the blue color toward green, for a typically cyan net color.^[5]
• Cyanobacteria (sometimes called blue-green algae) are an important link in the food chain.
• Cyanide derives its name from Prussian blue, a blue pigment containing the cyanide ion.

Cyan in human culture

Alternative Energy

• There is a company called Blue Green Pacific that sells small individual windmills to power private homes.

Architecture

• 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.

Astronomy

• The planet Uranus is cyan because of the abundance of methane in its atmosphere.

Computer games/video games

• There is a computer game company called Cyan Worlds (a.k.a., Cyan, Inc.).
• There is a Final Fantasy VI character named Cyan Garamonde.

Energy

• Natural gas (methane), used by many for home cooking on gas stoves, when burned has a cyan colored flame.

Interior design and industrial design

• The color cyan (called aqua by interior designers) was commonly used in the interior design of the 1950s in combination with either magenta or pink and black to give a modern feel to interiors (these colors were also popular for automobiles in the 1950s).

Medical

• Cyanosis is an abnormal blueness of the skin, usually a sign of poor oxygen intake. i.e the patient is "cyanotic".

Music

• There is a band called Cyan, a British progressive rock band from the 1980s and 1990s.

Panelology

• Cyan is the name of a character in the Norwegian comic strip Nemi.

Photography

• Cyanotype, or blueprint, a monochrome photographic printing process that predates the use of the word cyan as a color, yields a deep cyan-blue colored print based on the Prussian blue pigment.^[6]

See also

• List of colors

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. http://books.google.com/books?id=qFa_qP780RQC&pg=PA22&dq=%22cyan+blue%22+%22three+color+printing%22&lr=&as_brr=1&ei=pxItSKTOGaectAPy3OnvAg. 
2. ↑ Maerz and Paul The Dictionary of Color 1930 (see under Aqua in Index, Page 189)
3. ↑ Using HSL color space#Conversion from RGB to HSL or HSV, v=247/255
4. ↑ Tintbooks - Get Accurate CMYK Color Results For Your Printing Projects CMYK color tintbook:
5. ↑ Craig F. Bohren (2001). Clouds in a Glass of Beer: Simple Experiments in Atmospheric Physics. Courier Dover Publications. ISBN 0486417387. http://books.google.com/books?id=CZuNCZqtZZUC&pg=PA156&dq=absorption+scattering+water+blue+red&lr=&as_brr=3&ei=a684ScHhGI3WlQTM-_W7Bg. 
6. ↑ Mike Ware (1999). Cyanotype: the history, science and art of photographic printing in Prussian blue. NMSI Trading Ltd. ISBN 1900747073. http://books.google.com/books?id=C-7I69gFIbMC&pg=PA21&ots=alsMw9t0Kr&dq=cyanotype+prussian-blue+color&sig=s12O6C39teka_vg41EDxbflKMI4#PPA40,M1.