Light Science and Magic 4/e

We call the rate of fluctuation of the electromagnetic field its frequency, and we measure it with the unit called Hertz,

Light rays from a low-contrast source strike the subject from many different angles.

2.7 A shadow so soft that much of it is just barely visible is the result of a very large light source.

Light that is absorbed by the subject is never again seen as visible light. The absorbed energy still exists, but the subject emits it in an invisible form, usually heat

For single light sources, the size of that source is the primary factor influencing its contrast. A small light source is always a hard light source, and most large sources are soft ones. We see that the sun in Figure 2.4 occupies little area in the diagram, so it is a small light source. The cloud covers a greater area in Figure 2.6, making it a l

Materials such as white glass and thin paper scatter the light rays in many random, unpredictable directions as they pass through. This is called diffuse transmission

Absorption and reflection are both more major influences on

The third important characteristic of a photographic light is its contrast. A light source has high contrast if its rays all strike the subject from nearly the same angle.

Photographic lighting is more than just light. Lighting is a relationship between the light, the subject, and the viewer. If we want to say any more about lighting, we must talk about the subject.

All photons travel through space at the same speed, but the electromagnetic field of some photons fluctuates faster than that of others.