Barco Prometheus III, Installation Manual

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R5906897 /02 Prometheus III 173
After white point calibration proceed immediately with color gamut calibration.
15.3 Color gamut calibration
Color Gamut
Color Gamut is the entire range of reproducible colors by a particular device such as a projector. The entire
range of reproducible colors are typically defined so that horizontal and vertical directions describe saturation
and luminance changes, respectively. When a color is "out of gamut," it is not possible to reach that color by
the device.
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Image 15-1: Sample Chromaticity Diagram with Color Gamut of target device (1).
Why apply color correction?
During the post-production process of a film, a specific color space is applied. This color space is the Target
Color Gamut Data (TCGD). All movie content operates under that gamut. To ensure that in the cinema theater
the film is projected within the same color space as intended by the film industry, the color space of the
projector has to be corrected accordingly.
What has to be done?
The color coordinates for the projected primary colors must be measured on the screen. The values can be
different than those originally inside the projector due to reflection on the screen or due to the influence of the
glass between the projection booth and the theatre and even the projected colors are different from setup to
setup.
These measured color coordinates are references for the projector and will be entered so that the projector
knows how its colors are projected on the screen. This reference measurement (MCGD), together with the
delivered gamut file (TCGD) of the film will introduce a color correction so that the film will be projected with
the desired color target.
Color calibration