I’ve heard it, and even said it myself. Photography is all about the light.
Unless you are photographing the light source itself, such as stars, you are actually capturing reflected light to create the image. Now, before you say I am just getting nit picky, allow me to explain why this subtle difference is important.
Reflected light has a slightly different behavior. Different colors reflect a different amount of light. A classic example is the black color of a Groom’s Tux is one exposure, while the White gown of the Bride is a different exposure. This is because Black absorbs all colors and thus the reflected light is less, while white reflects all colors, and will reflect more light.
To make matters slightly more complicated, all lights are not created the same. Some light is a different color or temperature than others. For example, if you are shooting outside on the North side of a building, the light will be a “Cooler” color and add a blue hue to the image. Shade can also do this.
Inside, different light sources will change the color of what they reflect off. For example, incandescent bulbs generally have a “Warm” orange glow. Any object the light hits will have its color changed by this light. Knowing this color shift will happen will allow you to compensate for it in the picture, or use it as part of the image.
The last topic I want to mention is that light bends. Unless the light is coming from a “Collimated source” such as a laser, light will bend.
I know I have only touched on these topics. I will be writing a series of articles that will go into more depth of each of these. I just wanted to get you thinking about them now.
From the trenches, this is Scotty.