Yesterday, I was doing what photographers do, namely experimenting with semidiffuse light. Let’s start with a few definitions. Suppose that you are out on a bright cloudless day. The sun acts as a point source of light, just like a flashlamp. As a result, you get sharp shadows, which generally translates to high contrast in your photographs. This is nondiffuse light. Such light sources tend to create specular reflections off mirror like or shiny surfaces. On the other hand, if the sun is shining through clouds the light is bounced around until it is coming at you from all directions. There’s another way to create a diffuse light and that is by bouncing the light off a rough surface. Both of these reduce the contrast in the image.
So, what I’ve said is that there are two ways to diffuse or soften the light. First, you can pass it through a scattering medium like a cloud. Second, you can bounce it off a rough scattering surface.
Things can get really interesting when you start to work with semidiffuse light. Yesterday, I took the photograph in Figure 1, of highly intense directional light being diffused as it passed through sheer curtains. Notice how you can just make out some of the details behind the curtains, but that they are just a bit cloudy. The intensity of the light and its diffusion creates a very dreamy illumination that, to me anyway, screams out “morning.”
Figure 2, on the other hand, uses light that has filtered through a forest of leaves, thus losing some of its directionality. The shadows of the leaves and the window frame are fuzzed out. The light is then further diffused by the texture of the carpet. All in all it creates a very abstract sense.
Figure 3 combines both types of light. It is an early morning scene, taken a couple of weeks ago on my commute to work. The light is early morning light and very direct. Notice the sharply illuminated dew on the plants. But then notice how the morning fog diffuses the light creating dramatic sunbeams.
I am hoping that I have demonstrated the point that semidiffuse light can create very dramatic effects. And when you are really successful these effects can be quite magical.