FIELD TECHNIQUE: The Beauty of Bokeh

Story and photography by F.M. Kearney

© F.M. Kearney

© F.M. Kearney

Years ago, I referred to the out-focus parts of an image as, well, the out-of-focus parts of an image. Nowadays, it seems as though there’s a specific name for everything, and bokeh is the name for the aesthetic quality of the blur in the out-of-focus parts of an image produced by a lens. It has also been defined as “the way the lens renders out-of-focus points of light.”

After viewing several You Tube videos, I’m still not 100 percent sure how to correctly pronounce bokeh, but I can tell you it was popularized in Photo Techniques magazine in 1997. The word began showing up in photography books in 1998.

Perhaps the only thing that really matters is how to use it to enhance your photos.

Primarily used for the practical purpose of isolating a subject from a distracting background, the end result of bokeh can be pleasing and attractive. It is a common cinematic technique whereby the lights of a chaotic nighttime street scene are transformed into a colorful assemblage of ghostly, glowing orbs behind the actor.

The same concept applies to still photography. In order for any bokeh effects to appear, highlights—often ugly, harsh highlights—must be present in the background. This usually means shooting at the absolute worst time of the day under the worst possible lighting conditions.

Since Christmas isn’t too far away, I chose images of pine needles to accompany this article. However, I actually shot these photos on one of the hottest and sunniest days this past summer in the New York Botanical Garden.

I had spent most of the morning photographing daylilies while ducking and dodging the automatic sprinklers that popped up out of the ground with a seemingly sixth-sense knowledge of my exact location. By mid-morning, hardly anything in my immediate vicinity (including myself) was left unscathed by the impromptu showers. I then noticed that several nearby blue spruce pine trees had also sustained a good soaking. In the harsh lighting, they literally glistened with highlights— resembling tiny ice crystals on a cold winter’s day. The daylilies would have to wait.

The possibilities for beautiful bokeh were endless. I had to act fast though, because this early Christmas present wasn’t going to last long in the rising 80-degree temperatures. I set up my tripod close to one of the trees, careful not to dislodge too many of the water droplets. I composed a tight shot of a tiny branch, which I selected not so much for the amount of droplets on it, but for the number of droplets in the foreground and background. With an extension tube attached to my 70-200mm lens, I was able to render the droplets as soft balls of glowing light.

All bokeh is not created equal. Your aperture (more specifically, the shape of the diaphragm blades) determines the shape of the effects. It’s often stated that fast lenses with maximum apertures of f/2.8 or larger will produce the most rounded effects. I created the bokeh in these photos with an aperture setting of f/5.6. Although not absolute perfect circles, the highlights would have taken on a much more hexagonal shape had I closed down any further. Had I opened up any more, I would have begun sacrificing sharpness in the branch

© F.M. Kearney

© F.M. Kearney

One of the easiest ways to ensure that all the important elements of an image are in focus is to use the depth of field preview button. While depressing it, simply rack the aperture back and forth until the entire subject appears sharp. It might be a little difficult to discern just how sharp the subject actually is due to the darkened view. Even after allowing your eyes a few seconds to adjust to the darkness, there’s still no guarantee of accurate depth of field. In situations where critical sharpness is required, try bracketing your depth of field much like you would bracket your exposure. Having multiple images shot at different apertures is probably the best way to avoid any disappointments after the shoot.

With the holiday season approaching, creative use of the bokeh effect can produce some festive photos. Nothing says Christmas like a backdrop full of round, multi-colored globes of light behind your subject. Keep in mind, though, that it’s important not to overdo it. Just because you may have an f/2.8 (or wider) lens, doesn’t necessarily mean that you should automatically shoot at the widest aperture in every situation. It’s all about finding the “sweet spot” in a delicate balancing act of sharp subjects and soft bokeh. If the most important parts of your subject aren’t in perfect focus, all the beautiful bokeh in the world won’t help to save your image.


F.M. Kearney is a fine-art nature photographer specializing in unique floral and landscape images. To see more of his work, visit www.starlitecollection.com.