The aesthetic quality of blur produced in the out of focus parts of an image is known as bokeh (pronounced boh ka). Bokeh can also be defined as the way the lens produces out-of-focus points of light. This is the effect the lens design has on out-of-focus highlights in the background which mimic the lens aperture blade’s shape inside the lens. These may be perfect circles or they may appear as hexagonal shapes, with a good lens rendering these as soft looking circles, making the bokeh effect less distracting.
A different mindset needs to come into play when shooting landscapes which feature bokeh. If you swop f16 to shooting at f1.8 instead, then you need to consider your composition carefully as well. Using a wide angle, you will need to be nice and close to a foreground subject, just so that you can achieve a suitable bokeh effect. So, fill the bottom of the frame with this and focus carefully on this subject. Check the image afterwards for sharpness and use the depth-of-field preview if your camera has one. You may not be able to reduce your out-of-focus part of the frame to a series of soft circles, but you will produce a nice sense of depth with your results
You can read more about bokeh in my eGuide ‘Open Wide’, available as part of an e6 subscription or to purchase separately. www.e6subscription.co.uk