NEC SpectraView Reference 241, User Manual

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Profiler
User Manual
4.5.1 Color temperature
If you heat up a black body you will see that it radiates light. The spectral
distribution of the emitted light can be correlated with the temperature
of the black body. Any light‘s color temperature is the temperature in
kelvins (K) at which the heated black-body radiator matches the hue of
the light.
The lower the color temperature, the more yellowish/red- dish the
emitted light (e.g. incandescent lamp -> approximately 2800 K). The
higher the color temperature, the more blueish the emitted light (e.g. not
calibrated CRT monitor -> approx. 9300 K).
Color temperature only describes a certain color sensation, not a
specific spectral distribution. So, it’s unknown, how the measured x and
y values are composed spectrally. The CIE (Commission Internationale
de l‘Eclairage) have de- fined spectral distributions of standard lighting
situations, the most important of which is the D-series (D = Daylight).
D50
For the graphic arts industry, D50 is the standard for viewing and
comparing color. Also the color systems L*a*b* and XYZ as we use them
in graphic arts, are based on this illuminant. These are the reasons why
a computer monitor in an ICC- compliant working environment needs to
be calibrated to D50.
D50 spectral distribution curve
„D50“ spectral distribution curve of a CRT monitor