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Color Temperature. noun: the temperature at which a black body would emit radiation of the same color as a given object.
Lord William Thomson Kelvin was an accomplished mathematical physicist known for his advanced work in thermodynamics. He is credited with accurately determining the correct numerical value of absolute zero. (-273.15 C) Because of his contribution to science and engineering, absolute temperatures are stated in units of kelvin in his honor.
As photographers we don’t relate to “black bodies” and emitted radiation scientifically, but rather creatively by adjusting the white balance of our camera sensors electronically, or with color correction filters for emulsion based film.