How do you calculate color temperature?

1 Answer

1. Convert the RGB values to CIE tristimulus values (XYZ) as follows: X=(−0.14282)(R)+(1.54924)(G)+(−0.95641)(B) Y=(−0.32466)(R)+(1.57837)(G)+(−0.73191)(B)=Illuminance. Z=(−0.68202)(R)+(0.77073)(G)+(0.56332)(B)
2. Calculate the normalized chromaticity values: x=X/(X+Y+Z) y=Y/(X+Y+Z)
3. Compute the CCT value from:

How is CCT calculated?

The CCT of a light source can be determined by extending an isotemperature line from the blackbody locus out to the chromaticity coordinates of the source. For example, Point A in figure 8 represents a light source with chromaticity coordinates of (0.24, 0.59).

How do you calculate CIE chromaticity coordinates?

The calculation of the CIE chromaticity coordinates for a given colored object requires the multiplication of its spectral power at each wavelength times the weighting factor from each of the three color matching functions.

What is chromaticity CCT?

Correlated color temperature (CCT) is a measure of light source color appearance defined by the proximity of the light source’s chromaticity coordinates to the blackbody locus, as a single number rather than the two required to specify a chromaticity.

How do you convert wavelength to Kelvin?

It’s called Wien’s law. Wavelength (nanometers) = 3,000,000 / Col temp (Kelvin).

What is CCT 4000K?

CCT is defined in degrees Kelvin where a Warm light is around 2700K moving to Neutral White at around 4000K to Cool white, 5000K or more.

What is CCT value?

Color temperature defines the color appearance of a white LED. CCT is defined in degrees Kelvin; a warm light is around 2700K, moving to neutral white at around 4000K, and to cool white, at 5000K or more.

What is luminance and chromaticity?

Graphs of the x and y coordinates of lights are called chromaticity diagrams. Chromaticity diagrams show two of the three dimensions of color, the third being luminance.

Is color temperature the same as wavelength?

Colour temperature is related to black-body radiation, in theory the distribution of wavelengths of a light source of a certain colour temperature should resemble that of a black body of that temperature. So colour temperature is not exactly related to a wavelength, but to a distribution of wavelengths.

What CCT is soft white?

3000K
Soft White (3000K) The most common color temperature, Soft White is neutral, comfortable, and welcoming.

What is CCT 5000K?

Is 3000K brighter than 5000K?

K stands for Kelvin and represents the actual temperatures as measured on a Kelvin scale, Warm White and Cool White are represented by the letter ‘K’. Warm White is around 3000k, whereas Cool White is around 5000k. Lower on the scale is warmer and higher is cooler.

What is light chromaticity?

Chromaticity is a three-coordinate value that is mapped onto a color space, where light spectra are numerically described according to the stimulus of the eyes by light. This is done by the use of three color-matching functions that correspond to the peak wavelengths of the photoreceptor cones.

What is correlated color temperature in chromaticity diagram?

Each correlated color temperature (e.g. 6504 K CCT) is not a single point in a chromaticity diagram. Many points in a chromaticity diagram can have the same correlated color temperature.

Why are two-dimensional chromaticity coordinates associated with one-dimensional color temperature?

The ability to associate the two-dimensional chromaticity coordinates with the one-dimensional scale of color temperature along the Planckian locus enables a simpler communication of the visual appearance of nearly-white light.

What are the two parameters of chromaticity?

Chromaticity consists of two independent parameters, often specified as hue (h) and colorfulness (s), where the latter is alternatively called saturation, chroma, intensity, or excitation purity. This number of parameters follows from trichromacy of vision of most humans, which is assumed by most models in color science.

Color temperature can be approximated using just a pair of xy coordinates from CIE 1931. Use the formula below, or simply plug in the x and y values into our online calculator.