What the Heck is Bokeh?

It's pronounced boe-kay or boe-keh (boe like hoe, emphasis on first or both syllables), take your pick. Photographers talk about it all the time. So what is it and do you give a shit?

Well, I give a shit. Good bokeh is right up there with a good cigar in my list of good things, if maybe not quite so sensual. In simple terms (and it is a simple thing) bokeh refers to the out of focus area of your picture. So if it's out of focus, why does anyone care what it looks like? Well, it's how it's out of focus.

There is good bokeh and bad bokeh; good bokeh is usually kind of creamy and soft, bad boken is harsh and jagged. Some lenses that are decades old still have a reputation for good bokeh. Usually lenses with more blades (a lens opens and closes by rotating a series of rounded blades to make the opening - aperture - bigger or smaller), say nine, have better bokeh than those with say seven or fewer blades, which often produce poorer bokeh. But nothing is hard and fast - each lens has its own individual bokeh characteristic.

The camera plays a part as well. Full frame cameras often let you shoot with a larger aperture (say f/2.8) and larger apertures create more background blur in many shots, because they have a shallower depth of field. This often leads people to the erroneous conclusion that cameras with smaller sensors can't have good bokeh, something that just isn't so.

The two shots below are examples. Both are shot in raw with the Olypmus EM 1 and the Olympus 30mm macro lens (which produces my kind of bokeh, soft and creamy). The first shot is done as a standard macro shot, and the background blur is very evident, as the depth of field, or area in focus, is quite shallow - notice that even the busy pattern of the woven mat is fairly smooth - good bokeh :) The next shot is done with focus stacking, and you can just start to see the black tip of the flower petal starting to blur. Not bad bokeh, rather none. Both shots hand held, 400 ISO, 1/40 sec at f/3.5.

Is one of these better than the other? Not at all. The style of the first shot has become a norm in many people's minds, namely the blurry foregound and background of close ups. It is important to remember that bokeh is a trick of the camera - we don't see things like this. When you think about it, bokeh is one of the few camera 'tricks' that people accept as standard, with another being long exposures like the running water shot where the water is smoothly blurry. Many videographers now use digital still cameras with video taking ability (almost all of them nowadays) for their videos, precisely because they can produce bokeh - blurry backgrounds in shots that normal video cameras can't replicate.

Anyone with a decent camera and macro or zoom lens can take the first shot. The second one, not so - getting close to your subject ( I was about 3" away), shooting wide open and getting a broad depth of field is a tricky combination of things to do.

Anyway, first shot, good bokeh. There.