Page 22 - NyghtVision Boot Camp One Fill Edition
P. 22
3. The Mechanics of Light
Color is a function of both the angle with which ly leaves the light source the beam of light spreads or
the sun’s light strikes the earth and reflects from diffuses as we prefer to say. The beam might remain a
objects. The temperature of light (as the diagram bit more intense in the center than at the edges, but in
on the next page shows) is the measure we use to the end, the farther the beam moves from its source the
descibe the color that angle and reflection pro- more diffuse the entire beam becomes.
duces. We measure the color of light in degrees
Kelvin in honor of John Kelvin’s landmark work. There are many reasons why this happens. For the
most part, the density of the atmosphere and the angle
While the speed of light doesn’t change (186,000 at which the light strikes the surface of an object have
feet per second squared) the frequency or wave the most determining effect on how quickly a beam of
length does. The frequency of red light is consid- light diffuses. This is why the fourth question in our
erably longer than that of blue or white light. Fre- NyghtVision Methodology is so important.
quency is measured in degrees Kelvin. The LOW-
ER the degrees Kelvin, the longer the wave length. Light which is intense - a narrow beam - produces harsh
shadows and can bleach color from an object. The more
In the West, we think of light as a tight, narrow diffuse the light, the softer the shadows and often the
beam. In fact, despite how it looks, light isn’t a richer the colors.
tight bean of energy at all. If we could look at
a beam of light we would see that as it actual- As the diagram on the right shows, the steeper the angle
of reflection, the more pale the overall colors in a scene.
22 Boot Camp, Part 1
