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Color and Light · entry 50 of 52
Cameras capture color by filtering light through red, green, and blue sensors.
The longer version
A sensor records only brightness, so each pixel is covered by a tiny red, green, or blue filter in a repeating mosaic. Software then estimates the missing two values for every pixel from its neighbours, reconstructing a full-colour image from partial measurements.
The arrangement uses twice as many green filters as red or blue, because human brightness perception leans heavily on the middle of the spectrum. The reconstruction is not perfect and can produce false colour on fine repeated patterns, an artifact called moire. Infrared is normally blocked by a filter in front of the sensor.
Where this entry sits
These facts explore how light behaves and how human eyes turn it into the colors we see. Along the way you meet rainbows, prisms, mirrors, shadows, lasers, and optical tricks that fool our vision every day. The full list sits on the Color and Light page, where every entry is listed in order.
More From Color and Light
Eight more entriesPrinted images use cyan, magenta, yellow, and black ink to reproduce many colors.
Read 52Stop signals are usually red because the color stands out against most natural backgrounds.
Read 1The human eye detects color using three types of cone cells sensitive to red, green, and blue light.
Read 2Rainbows form when sunlight bends and reflects inside countless tiny water droplets in the air.
Read 3A prism splits white light into a spectrum because each wavelength bends by a different amount.
Read 4Shadows appear when an opaque object blocks light from reaching a surface behind it.
Read 5Mirrors reflect light because a thin metal coating bounces most incoming rays straight back.
Read 6A red apple looks red because its skin absorbs most colors and reflects red wavelengths.
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