Resolution (f11)

Canon 14mm at f11 (centre) Sigma 12-24mm at f11 (centre) Nikon 14mm at f11 (centre)

By f11 the Nikon has largely overcome its centre frame handicap, but even here it doesn’t quite have the bite of either the Sigma or the Canon which are pretty much level pegging – perhaps the Canon is again a little sharper.

Canon 14mm at f11 (corner) Sigma 12-24mm at f11 (corner) Nikon 14mm at f11 (corner)

The other corner conveniently gives us a chromatic aberration yardstick. A caveat here: the Sigma exposure was about half a stop lighter than the other two, so it appears to have retained less high frequency information. In fact its corner performance at this aperture is very similar to the Canon, as we’ll see in a moment. The results speak for themselves: amazing CA control from the Sigma, excellent for the Nikon, and less impressive for the Canon.

Fortunately we have four corners to play with:

Canon 14mm at f11 (corner) Sigma 12-24mm at f11 (corner) Nikon 14mm at f11 (corner)

Excellent near-field corner performance from the Sigma: the Canon in fact is least comfortable at close range: these samples represent a subject distance of about 1.5m.