Sharpness at 70mm

For this test, the Carl Zeiss Vario Tessar T* FE 24-70mm F4 ZA OSS lens was attached to a Sony A7 body, which in turn was mounted on a sturdy tripod. Exposure delay mode was activated. Tonal and colour variances across the crops are due to changes in natural light during the session.

The full frame at 70mm

Centre sharpness is impressively high through from f/5.6 to f/16, with f/22 being adversely affected by diffraction. The edges are not quite as sharp as the centre, with f/8-16 producing the sharpest results.

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