Autofocus Converted Contax N Test: 17-35mm f2.8

Contax N 17-35mm f2.8 v Nikon AFS 17-35mm f2.8

Performance at 17mm: f5.6 (Centre Frame)

Contax N 17-35mm at 17mm/f5.6	Nikon 17-35mm AFS at 17mm/f5.6
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Performance at 17mm: f5.6 (10mm off-centre, right side)

Contax N 17-35mm at 17mm/f5.6	Nikon 17-35mm AFS at 17mm/f5.6
0 points	1 point

Performance at 17mm: f5.6 (Upper left corner)

Contax N 17-35mm at 17mm/f5.6	Nikon 17-35mm AFS at 17mm/f5.6
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There's barely any point stopping the Contax down further than this because, amazingly, at 17mm / f5.6 it renders a corner equally as sharp as the centre of frame, which makes it practically unique at this focal length. But that irregularity in the inner ring of the image circle persists, even here, two stops down. The shortcoming is acutely exploited by the Nikon, which displays a diametrically opposite failing: it struggles to render clean centre frames and corners, but excels precisely where the Contax stumbles.

Note also the strong blue/yellow lateral CA in the Nikon shot, and the Contax' uncharacteristic tendency to warm colour: not at all Teutonic. Again, here bear in mind that the Nikon has a slight tendency to render on the cool side.