Chapter 2. What Is Color?

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Chapter 2. What Is Color ?

Without color, our perception of the world would be much different. Colors are everywhere. We have brown chairs, blue skies, red cars , yellow bananas, black belts, white snowflakes , and many more things around us that have unique colors. Most people are accustomed to color because we have experienced it since we were born.

But what is color? As youngsters, we are taught that red is red and green is green. But many people are color-blind and can't even see red or green at all. So we define color as the visual perception of a specific variation that most of us can agree upon. Interestingly though, if you were to see out of another person's eyes, you would probably be in shock since everything would be tinted and look surreal due to slight frequency shifting in the response of your eyes to his/her eyes. This brings new meaning to "beauty is in the eye of the beholder."

In the previous chapter, you learned all about electromagnetic waves, which are classified within the electromagnetic spectrum. Each wave has a different frequency and wavelength. Visual lightmade up of red, orange, yellow, green, blue, and violetis a specific segment of the electromagnetic spectrum. An important point to note is that our eyes can interpret many variations of colors, but they're mostly sensitive to green. Visual light is illustrated in Figure 2.1note how it is a very small portion of the whole spectrum.

Figure 2.1. Visible light is made up of red,orange,yellow,green,blue,and violet .The spectrum here moves (from left to right) from low frequency,long wavelength to high fre- quency,short wavelength.

When an electromagnetic wave travels and interacts with an object, it causes some of the natural frequencies of the object to vibrate. Different objects have different natural frequencies for absorbing and emitting energy. In certain objects, where the amplitude of the vibrating electrons is high, some of the energy is absorbed. If the incoming frequencies are below a certain threshold, some of the light is reflected.

Normally, some of the energy would be absorbed into the object and some would be reflected. If an object absorbs all colors except green, the object appears green. If the object absorbs all colors except red, the object will appear red. If the object absorbs all colors and reflects nothing, it will appear black. So the color of an object is determined by the color that reflects .

The color of a transparent object is based on the natural frequency of the object in conjunction with the frequency of incoming electromagnetic wave. Clear glass transmits the color the exact same way the wave is entered in the object. This is because almost all the visual frequencies are passed through the object perfectly well. If the glass absorbs all the visual light but blue, it will not only appear blue but will transmit blue as well. This is a very nice effect; as you know if you've ever been to a club with color spotlights , you can see all types of colors projected on the walls and floors.

The visible frequencies (colors of the rainbow) of light added together produce white; however, strangely enough, red, green, and blue alone can also produce white. What this means is that the visible spectrum can be simplified into red, green, and blue regions .

When mixed together, these separate components can generate almost all the colors of the visual spectrum. This is a much simpler method of defining colors. When one component mixes with another, they create a new color. For example, if you mix red and green you produce yellow, or if you mix blue and green you produce light blue. This method of defining colors for red, green, and blue is called the additive primary colors method, as shown in Figure 2.2.

Figure 2.2. The additive primary colors method uses red,green,and blue as a starting point for all other colors.

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