Sometimes when I haven’t taken any pictures in awhile—like, say, today—I push myself a little harder and find something, even something simple and ordinary, to shoot. It’s a kind of workout, but the only things that get any exercise are my shutter finger and, in the best cases, my mind.
The nearest thing I could find today was in my front yard. The roses have exploded in color bursts I don’t remember from previous springs. I thought for a minute and figured I could work on depth of field.
Depth of field is a term of art in photography, referring to how much focus is in a picture. If width is the first dimension, and height is the second dimension, depth is the third dimension. But in a two-dimensional medium like photography, that third dimension is an illusion. Shallow depth of field means only a small part of the picture is in focus. It could be the foreground, the mid-ground, or the background. In deep depth of field, all three would be in focus.
There are two ways to monkey with the depth of field. One is mechanical, and the other digital. In the mechanical manner, a bigger lens aperture will make for shallower depth of field, and a smaller aperture will make for deeper depth of field. The digital manner relies on computer software to do the focus trick.
Both methods have their virtues, and both have their drawbacks. For instance, the mechanical method has a more realistic look, but it can take some experimentation with the dials on the camera. Similarly, the software approach can alter depth of field in situations where the camera may have had problems, but it takes some aesthetic skill and a steady hand to mark the parts of the picture that require the software’s attention.