Sharpness at 70mm

The sharpness tests for this review were carried out using a real-world subject rather than a test chart. The Canon EF 24-70mm f/2.8L II USM lens was attached to a Canon 5D Mark III body, which in turn was mounted on a sturdy tripod. Self-timer mode was activated. Slight tonal changes are due to slight changes in natural light during the session.

The full frame at 70mm

Center sharpness isn't great from f/2.8-f/5.6, only becoming excellent from f/8-f/16, with sharpness beginning to drop-off at f/22 due to diffraction. Edge sharpness is also best between f/8-f/16.

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