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Cha p te r
S i x

FIGURE 6.12 Two-dimensional mapping of color in a space.

3
Theoretically, there would be 256 , or 16,777,216, unique positions
in its color space for defining color (Fig. 6.13). In reality, the actual
number of colors a sensor can reliably distinguish is much less
because of optical noise and practical limitations of the design.
The device compares the RGB colors it observes to the internally
learned standard. Each time a standard color is relearned, it essen-
tially recalibrates the sensor.

6.3.4 Color Comparators and True Color Measuring
Instruments
If the learned color is initially defined by a color spectrometer, the
fuzzy logic color sensor (comparator) can be installed in conjunction
with it. The color sensor can learn the same area that the spectrometer
has read, thereby equating its learned standard to the absolute color.
By using the color sensor in this manner, a temporary correlation to
an absolute color standard can be established (Fig. 6.14). This permits