Sharpness Cont... 2

Sharpness at 20mm

The sharpness tests for this review were carried out using a real-world subject rather than a test chart. The Tokina AT-X 16-28mm F2.8 Pro FX lens was attached to a Canon EOS 5D mark II DSLR camera, which in turn was mounted on a sturdy tripod. The self-timer was used to avoid any vibrations from pressing the shutter release. Slight tonal changes are due to slight changes in natural light during the session.

The full frame at 20mm

Centre sharpness at 20mm is best at f/8, while the edges are acceptably sharp from f/11 to f/16.

Aperture	Centre Crop	Edge Crop
f.2.8
f/4
f/5.6
f/8
f/11
f/16
f/22