SHOT CRAFT CIE-XYZ 1931 color gamut diagram illustrates Kelvin temperature (outer edge), Planckian curve (lower third) and correlated color temperatures (lines across curve). most sensitive to. Toward the center, the colors merge to create secondary colors. The lower third is the point where all the colors mix additively into white light. Tying It All Together Along this lower-third portion of the CIE graph, starting from the far-left side, we can find the plot of a specific curve of colors starting at about 600 nanometers and moving in an arc toward the center of the chart. This is the Planckian locus, along which you can see the Kelvin color-temperature range. Motion-picture film emulsion and digital-imaging sensors are designed to be sensitive to this Planckian curve of color temperatures, with a fundamental basis at about 6,500K daylight (aka " D65 " ) or 3,200K color temperatures. Light sources that generate a color temperature that falls along this Planckian locus in the CIE XYZ color space will have excellent color fidelity when recorded by film or digital sensors. 16 / JANUARY 2021