The Rainbow Story
The technical term “color science” deals
with the hues (red, orange, yellow…), the brightnesses, and the intensities or
saturation (white-to-pink-to-shocking pink-to-scarlet) of the rays of light by
which we see. It deals also with their measurement and classification. Even
after long personal involvement, to me, “color science” carries no
suggestion of the brilliance of color awaiting the proud possessor of a normal
human visual system, as he or she uses it in normal living. While waiting, it is
well to recognize that, as Isaac Newton pointed out, “the rays are not
colored.” The rays of light have physical differences, measurable in the
laboratory, but there is no color in them until they are responded to in an
intricate manner by the visual system. Thus the visual system
instantaneously classifies each of them – tens of thousands of them per second
– in all three dimensions: hue, brightness and saturation.
Through the following visual experience it was made clear to the writer that the range of brilliance of perceived color is vast indeed. This experience may have encompassed close to the full range, vouchsafed to human experience, of all three dimensions of color. It happened as follows.
A few years ago my fiancé and I drove to southern Florida in January, to attend a meeting on color, akin to the subject of this website. Very early the first morning after the close of the meeting, we drove south and then west, to have another look at the Everglades. The sun was up, and bright, but low behind us at the eastern horizon. Ahead of us and slightly to the right were scattered several large tank trucks, pumping irrigation water in wide, high arcs, onto growing vegetable plants. As we approached slowly, it was evident that one of the arcs was going to splash onto the roadway at about the instant of our reaching it. So it happened. For a split second, we were surrounded by – immersed in – a rainbow of its usual colors, but brilliant to the point of being almost blinding. In that moment, all of the spectral colors flashed by. The experience was immediately recognizable as once-in-a-lifetime.