Cyan is a vivid blue-green color that is often associated with cool, calming sensations. In the world of light and color, cyan is made by combining the primary colors green and blue light. When these two colors are mixed together in equal proportions, the resulting secondary color is cyan. Understanding the basics of how light and color work together can help explain what light makes cyan.
The additive color model
In order to understand what makes cyan, it’s important to first look at the additive color model. This model deals with light and is used for computer screens, projectors, and other display technologies that emit light.
The primary colors in the additive model are red, green, and blue. These are known as the three additive primaries. When you look at a computer screen very closely, you can see that it is made up of tiny red, green, and blue sub-pixels. By adjusting the brightness of each sub-pixel, screens can display a wide range of colors.
| Color | Red | Green | Blue |
|---|---|---|---|
| Red | 255 | 0 | 0 |
| Green | 0 | 255 | 0 |
| Blue | 0 | 0 | 255 |
In the additive color model, mixing red, green and blue light together in equal amounts produces white light. The table above shows the red, green, and blue values for the additive primaries. When you mix red and green light together, you get yellow. Mixing green and blue makes cyan. And mixing blue and red light together produces magenta.
Making cyan by combining green and blue
Based on the additive color model, it’s clear that cyan is created by mixing green and blue light together. In specific ratios, the green and blue blending results in a vibrant cyan.
On a computer screen displaying an image in full color, adjusting the RGB values allows you to “make” precise shades of cyan. For a pure vivid cyan, you would set the red value to 0, the green value to 255, and the blue value also to 255. This mixes the full brightness of green and blue, without any red contaminating the color.
| Color | Red | Green | Blue |
|---|---|---|---|
| Cyan | 0 | 255 | 255 |
The reason cyan is such a bright, lively color is because it combines the brightness of the green and blue wavelengths without any dilution from the red. Your eye perceives this vivid blue-green secondary color when the full intensities of the green and blue primaries are blended.
Cyan in print and paint
The same principle of combining green and blue light applies to creating cyan colors with print pigments and paints. However, instead of using an additive model, print and paint colors use the subtractive color method.
The subtractive primaries are cyan, magenta, and yellow. These are the pigment colors that absorb, or subtract, parts of the visible spectrum. Cyan pigment absorbs the red areas of the light spectrum, reflecting back green and blue.
When cyan paint or dye is used for printing, you are starting with a white surface. The white contains a full spectrum of visible light waves. The cyan subtracts the red areas of the spectrum, leaving the green and blue wavelengths to be reflected back to your eyes. This gives the appearance of a vibrant cyan color.
Cyan and light wavelength
To understand cyan light even further, it helps to think about specific wavelengths. Visible light from the sun contains a continuous spectrum of wavelengths, spanning from about 400 nanometers (violet) to 700 nanometers (red). Green light has wavelengths of around 500-565 nm, while blue wavelengths are around 435-500 nm.
When you combine these ranges, cyan (green-blue) has an overall wavelength signature of roughly 485-565 nm. A vivid cyan color will strongly reflect these mid-range wavelengths, while absorbing the longer red wavelengths (above 565 nm) and the shorter violet wavelengths (below 485 nm).
Cyan in nature
In the natural world, cyan is relatively rare among plant and animal pigments. Most organic compounds tend to absorb in the blue and red areas, leaving shades of yellow, orange, and brown.
However, there are some striking examples of cyan and blue-green colors in nature:
- The ocean often appears cyan, due to absorption of longer red wavelengths by water molecules.
- Cyanobacteria obtain their colors from phycobiliproteins, used to capture light energy.
- Butterfly wings can feature stunning blue and green iridescence, created through photonic nanostructures.
- Parrots and macaws get vibrant plumage colors from psittacofulvins, a class of pigments.
- The poison dart frog has a bright blue-green toxic skin created by unique pigments.
While relatively rare in nature, living things can produce cyan through specialized optical structures and pigment molecules. These provide cyan colors that stand out against the dominant yellow-oranges of the natural landscape.
Digital cyan
In the digital world, cyan as a color is defined with specific RGB values. This allows consistent representation of cyan across different programs and devices.
In HTML and CSS, a pure cyan is defined as #00FFFF. This pairs a green value of #00FF00 and blue value of #0000FF in equal amounts.
In Adobe design programs, the default cyan color has the following values:
- RGB – Red 0, Green 255, Blue 255
- CMYK – Cyan 100%, Magenta 0%, Yellow 0%, Black 0%
- HSB – Hue 180°, Saturation 100%, Brightness 100%
- Hex code – #00FFFF
These precise specifications allow digital cyan to be rendered accurately and consistently for web, print, video, and other digital media applications.
Cyan printing and pigments
In commercial printing processes, cyan is one of the primary colors used, along with magenta, yellow, and black (CMYK). Cyan ink reflects both green and blue light while absorbing wavelengths in the red.
Cyan printing ink typically contains high-stability organic pigments. Some examples of popular cyan pigments include:
- Phthalocyanine PB15:3 – a bright blue-green synthetic pigment
- Victoria Blue – a triarylmethane dye used for textile printing
- Phthalocyanine Green G – a transparent green pigment combined to make process cyan
By selecting pigments with specific spectral properties, print processes can achieve a consistent, vivid cyan tone. Overprinted with magenta and yellow inks, the cyan allows full-color images to be reproduced.
Conclusion
In summary, cyan is created by combining green and blue colored light sources in the additive color method. In nature, cyan appears rarely but can be produced by specialized structures and pigments. In print processes, display screens, and digital art, precise cyan colors are defined with RGB values, CMYK formulations, and color codes. Cyan results from pairing green and blue primary colors, whether in light, pigment, or code. Understanding the mixes needed to produce cyan helps explain why this vivid color has become so popular and widely used.