|Going Wildly Wide: AFS 12-24 mm f/4 G ED IF DX Nikkor Reviewed|
|by Bjørn Rørslett|
5. When the image is out of focus
Bokeh relates to the fashion in which the out-of-focus areas of the image is rendered. The word itself is of Japanese origin, and the importance and even existence of 'good' bokeh have been a hotly debated topic for years. Suffice to say that some lenses have it, some not and some like it hot.
Amongst the Nikkors, the AFD 85 mm f/1.4 lens has long enjoyed a well-deserved reputation for its superb bokeh. Thus, in images taken with that lens, the sharply focused subject is set against a pleasingly silky smooth background. The transition from in-focus to out-of-focus occurs gradually. A good example of poor bokeh is the AFS 300 mm f/2.8 Nikkor, which despite its excellent sharpness tends towards producing hash backgrounds when it is stopped down. A large number of aperture blades gives a more circular opening when the lens is stopped down, but this in itself is not sufficient as witnessed by the 85 and 300 mm Nikkors both of which have a 9-bladed aperture.
The 12-24 DX has only 7-bladed aperture and one may wonder whether this is enough to provide good bokeh. I looked into this when I started using my personal 12-24 DX lens, and can assure you are unlikely to encounter any disaster in the bokeh area with this lens. The images are very smooth and the transition from focused to non-focused zones in the image occurs very gradual and gentle. In fact, with the low f/4 "speed" and short focal lengths of this lens, it is quite hard not to get most of the scene into more or less acceptable focus anyway.