Bokeh. What the hell is it?

Bokeh. Have you heard this term bandied about in conversations while looking at a photo, listened while someone proclaimed that the bokeh in a photo was good or bad, but you’ve been too embarrassed to ask just what it is? It’s something every photographer should understand because it affects your image. And whether you know it or not, you’ve probably evaluated the bokeh in your own photos. Well hide your shame no longer. After reading this article, you will be able to hold your head high and raise your nose as you talk about the bokeh in your next photo.

So, what is bokeh, exactly? Simply, when someone talks about “bokeh” they are referring to the out of focus portion of a photograph, usually the background, especially highlights in the background that can appear as blurry circles. Bokeh comes from the Japanese word boke which means blur (Wikipedia: Bokeh). When photographers discuss bokeh they are talking about its aesthetic quality. And as silly as it might seem, bokeh can be an important consideration in many photographs.

Smooth bokeh
Smooth, delicious bokeh. 1/60s @ f/2.8

But isn’t blur, well, blur? Well, no. Different scenes shot with different cameras and different lenses at different apertures all produce different bokeh. Any one of those factors can change its character. Now, obviously, bokeh is subjective. Many people don’t care about it at all. But many others consider bokeh an important part of a photograph, particularly in portrait photography. In fact, some people consider it so important that they’ll buy thousand dollar lenses that give you a little extra control (Nikon, for example, has a couple of lenses with “defocus control” that affects the bokeh).

Bokeh example
Bokeh example. 1/400s @ f/5.6

The shape of out-of-focus highlights is influenced by the shape of the aperture opening in the lens. The aperture is made of a diaphragm with several blades that allow it to open and close. The more blades, the rounder the opening. Some lenses even have curved rather than straight edges on the diaphragm blades to make the opening more like a perfect circle.

Christmas lights
I rather like how the christmas lights stand out in this. 1/125s @ f/2

Only you can decide if you like a particular photo’s bokeh or not. It’s a matter of taste. But in general, smooth bokeh with blurry, round highlights, soft edges and uniform brightness is preferred over harsh bokeh with polygonal highlights and hard edges. One thing you definitely don’t want bokeh to do is steal attention away from your subject by being distracting (unless, of course, your subject is the bokeh itself). If you’ve got distracting bokeh in your image, here are a couple of things you can do:

  • Open the aperture. The wider the aperture opening, the fuzzier the background will become.
  • Close the aperture. The smaller the opening, the sharper everything will be. If nothing is out of focus, there is no bokeh.
  • Change the distance between you and your subject. Bokeh looks different at different distances.
  • Compose your scene so that there are no bright highlights in the background. Bright highlights are often the culprit when a photo is said to have “bad” or distracting bokeh.
  • Change lenses. Different lenses will produce different bokeh. It’s for this reason that some lenses are said to have “good” bokeh.

Do you have any bokeh tips or opinions? Please share them in the comment space below.

Update: Photodoto reader, Dave, sends in an example of what he considers really bad bokeh. Below is portion of the background from that photo:

Bad bokeh
Bad bokeh

Notice the odd, distracting texture from hard edges in the highlights. Thanks, Dave!

By John Watson

John is the original founder of Photodoto, but after running it for 4 years he had to focus on different things. If you're interested in what John has been up to recently, you can check is personal blog or browse his photo blog.