Bokeh is one of those photographic qualities that everybody has a hard time agreeing on – photogs will debate it to death, but when they see a good example of it, they know it!  By definition, bokeh is simply the out-of-focus portion of a photograph (usually in the background).

“Good bokeh” is highly sought after, whilst “bad bokeh” is generally disparaged – but what actually makes bokeh good or bad?  That ends up being a tricky question, and the answer will vary quite a bit depending on who you ask.  But in general th softer, creamier, and more pleasantly blurred a bokeh is, the better it is appreciated.

So what can you do to get better bokeh?

1.  Shoot wide open

Since bokeh is a quality of the out-of-focus (OOF) area, then the more you can throw the background OOF, the better.  Lenses with wide, fast apertures are very well suited to this – think at least f/2.8, with f/1.8 and faster being even better.  You essentially want to have your subject just within the range of focus, and everything else falling off as fast as possible to maximize the OOF background.

50mm @ f/2

2.  Compose for a better distance ratio

“Distance ratio” sounds complex, but what it really means is that the ideal setup is for there to me a small distance between the camera and the subject, and a much larger distance between the subject and the background.  By keeping the subject near to the camera, and far from the BG, you can maximize the OOF effect on the BG (whereas reversing this ratio will lead to a BG that’s much more in-focus than you probably want.)

Good distance ratio; model much farther from BG than from camera

3.  Pick a bokeh-friendly background

If you’ve got a gentle background with consistent colors and lighting, composed of softer shapes, you’re more likely to have a nice bokeh.  BGs with lots of sharp angles and lines and abrupt changes between colors or lighting conditions aren’t going to look as nice.

4.  Shoot with a telephoto lens

Telephoto lenses are masters of bokeh, which is why so many portrait photographers prefer them.  It’s a physical property of telephoto optics that makes them work so well – even bypassing the requirement for wide-open apertures to some extent.  Check out images taken with the 70-200 f/4 for some great bokeh, or better yet, check out super-telephoto bird and wildlife shots.  So long as there’s a good distance ratio, you’ll see some incredibly blurred BGs, even at apertures of f/5.6.

Bokeh @ 400mm

5.  Use a more bokeh-friendly lens

Not to dump the responsibility on the gear, but it is a fact that there are some lenses that simply produce better bokeh than others.  This isn’t a feature that will be listed on manufacturer specification pages – if you want to find out about the bokeh qualities of a potential lens, you should search for some user opinions.  Photography forums are your friend – there are always photogs there who love sharing and debating these somewhat-esoteric qualities.  Then check out Flickr for user groups who use the lens and see the images for yourself.