ProPhoto RGB color space

From Wikipedia, the free encyclopedia

CIE 1931 xy chromaticity diagram showing the gamut of the ProPhoto RGB color space and location of the primaries. The D50 white point is shown in the center. The areas of the triangle that are outside the coloured area are imaginary colours.

The ProPhoto RGB color space is an RGB color space, developed by Kodak, that offers an especially large gamut designed for use with photographic output in mind. The ProPhoto RGB color space encompasses over 90% of the visible colors specified by the CIE L*a*b* color space, making ProPhoto even larger than the Adobe Wide Gamut RGB color space. One of the downsides to this color space is that approximately 13% of the representable colors are imaginary colors that do not exist and are not visible colors. This means that potential color accuracy is wasted for reserving these unnecessary colors.

When working in color spaces with such a large gamut, it is recommended to work in 16-bit color depth to avoid posterization effects. This will occur more frequently in 8-bit modes as the gradient steps are much larger.