Lessons Learned: Selective focus

When the creative "focus" of your image calls for separating a single subject from a busy (but appropriate) background, selective focus can turn an average snapshot into a refined image.

In this case, the pond lily with its delicate lavender hued petals and brilliant yellow center is our primary subject. The dark water, framed with lily pads, fallen leaves and other plantlife, forms a dark, background for the flower that's complementary both in color and context.

If we shot it straight with lots of depth of field, we'd get a pretty busy picture. But by using selective focus, we can render the background softer-focused than the flower, using it for context for the main subject.

Depth of Field is the distance, foreground to background, where the image is acceptably sharp and focused. It's controlled by two factors, the focal length of the lens (depth of field gets shallower with longer lenses) and the aperture setting (depth of field gets shallower with wider apertures).

In this picture, I zoomed out to a moderate telephoto length, and kept the aperture at a low number (probably around f/4 or f/5.6). Luckily depth of field is visible when you're focusing the picture, so you can set it visually. Keep in mind that if you make a print, a larger print will also have an effect of shortening the depth of field at a given viewing distance, so plan accordingly if that's your intent for the image.