The basic tools of lighting are principles, not hardware. Shakespeare’s tool was the Elizabethan English language, not a quill pen.
Lighting is the language of photography. Patterns of light convey information just as surely as spoken words. The information that light conveys is clear and specific. It includes definite statements, such as “The bark of this tree is rough” or “This utensil is made of stainless steel, but that one is sterling.”
The three principles we have just given are statements of physical laws that have not changed since the beginning of the universe. They have nothing to do with style, taste, or fad. The timelessness of these principles is exactly what makes them so useful.
The most important part of good lighting happens before we turn on the first lights. This planning can take many days or it can happen a fraction of a second before pressing the shutter release. It does not matter when you plan how long it takes, as long as you get the planning done. The more you can accomplish with you head, the less work you have to do with your hands — you can think faster than you can move.
Inexperienced photographers work best with the camera with which they are familiar. Experienced photographers work best with the camera they like. These human factors sometimes have more to do with the success of a photograph than the purely technical principles.
Light is a type of energy called electromagnetic radiation. Electromagnetic radiation travels through space in tiny “bundles” called photons. A photon is pure energy and has no mass.
The energy of the photon produces an electromagnetic field around the photon. A field is invisible and cannot be detected unless there is a material object in the field on which it can exert a force.
Unlike the field around the magnet, the electromagnetic field around the photon is not constant in strength. Instead, it fluctuates as the photo travels. The field around a photon is positive half of the time and negative the rest of the time. The average charge of the two states is zero.
The electrical component is perpendicular to the magnetic one.
All photons travel through space at the same speed, but the electromagnetic field of some photons fluctuates faster than that of others. The more energy a photon has, the faster the fluctuation. Human eyes can see the effect of this difference in photon energy levels and in the rate of field fluctuation. We call the effect color. Red light, for example, has less energy than blue light.
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.
Reflection is light striking a subject and bouncing off. Reflection makes vision possible. We do not see objects; we see light. Because most objects produce no light, their visibility depends entirely on light reflected from them. We do not need to show you a photograph of reflection. Almost any picture you have on hand will serve that purpose.