Beautiful bokeh

‘Bokeh’ comes from the Japanese term for the aesthetic quality of the blur produced in the out-of-focus parts of an image. It’s caused by lights taking on the shape of the aperture opening. It’s subjective, but the more rounded the aperture, the ‘creamier’ and more attractive the bokeh will be. Expensive lenses have curved aperture blades to accentuate this, while a greater number of aperture blades results in a smoother bokeh too. A smaller number of non-curved blades results in harsher, more geometric-shaped bokeh.