0BOKEH
Bokeh is defined as “the effect of a soft out-of-focus background that you get when shooting a subject, using a fast lens, at the widest aperture, such as f/2.8 or wider.” Simply put, bokeh is the pleasing or aesthetic quality of out-of-focus blur in a photograph.
Although bokeh is actually a characteristic of a photograph, the lens used determines the shape and size of the visible bokeh. Usually seen more in highlights, bokeh is affected by the shape of the diaphragm blades (the aperture) of the lens. A lens with more circular shaped blades will have rounder, softer orbs of out-of-focus highlights, whereas a lens with an aperture that is more hexagonal in shape will reflect that shape in the highlights.
Achieving bokeh in your Images:
To achieve bokeh in an image, you need to use a fast lens—the faster the better. You’ll want to use a lens with at least an f/2.8 aperture, with faster apertures of f/2, f/1.8 or f/1.4 being ideal. Many photographers like to use fast prime lenses when shooting photographs that they want visible bokeh in.
You’ll want to shoot with the lens wide open, so you’ll want to use a shooting mode of Aperture Priority or Manual. Manual gives you the ability to choose both your aperture and shutter speed, whereas Aperture Priority allows you to choose the f/stop while the camera chooses the appropriate shutter speed for the exposure. You could also use the flexible program mode, choosing the widest possible aperture/shutter speed combination.
Don't worry if you don't own a very fast lens. By increasing the distance between the background and your subject, you can see bokeh in images that are shot at smaller apertures like f/8.
To increase the likelihood of visible bokeh in your photographs, increase the distance between your subject and the background. You can do this by decreasing the distance between the camera and subject. The more shallow the depth-of-field, or further the background is, the more out-of-focus it will be. Highlights hitting the background will show more visible bokeh too, so if you’re using a backlight, side light or a hair light, the bokeh may be more pleasing to the eye.
