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

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

Performance at 24mm: f2.8 (Centre Frame)

At 24mm we stir into the mix the winner of the 24mm World Cup: the Canon 24mm f1.4 L.

Contax N 17-35mm at 24mm/f2.8	Nikon 17-35mm AFS at 24mm/f2.8	Canon 24mm f1.4 L / f2.8
1 point	2 points	0 points

If you've seen the final of the 24mm group test, you'll know that the Canon overcame the substantial handicap of suffering the same focal plane variation we've seen in both the Nikon and Contax zooms. This sample, currently being examined by Canon, has a pronounced soft spot centre frame up to f5.6 – the opposite of a number of other reviews which have demonstrated excellent centre frame performance but soft corners. As you'll see, this one is anything but. Up in the 24mm range, the Nikon has reversed the centre frame advantage enjoyed by the Contax in the 17-21mm range, and now looks a fraction sharper wide open.

Performance at 24mm: f2.8 (10mm off-centre, left side)

Contax N 17-35mm at 24mm/f2.8	Nikon 17-35mm AFS at 24mm/f2.8	Canon 24mm f1.4 L / f2.8
0 points	1 point	2 points

Performance at 24mm: f2.8 (Upper left corner)

Contax N 17-35mm at 24mm/f2.8	Nikon 17-35mm AFS at 24mm/f2.8	Canon 24mm f1.4 L / f2.8
0 points	1 point	2 points

That's how to render a corner at f2.8: the Canon prime again excels everywhere except bang in the middle, even though we're two stops down from max aperture here. The Contax N 17-35mm isn't really happy at this focal length and struggles to outperform the Nikon in any department.