Sharpness at 100mm

For this test, the Panasonic Lumix S PRO 70-200mm F2.8 O.I.S. lens was attached to a Panasonic S1R body, which was in turn mounted to a sturdy tripod. Exposure delay mode was activated and image stabilisation turned off. Tonal and colour variance across the crops are due to change in natural light during the session.

The full frame at 100mm

With a constant maximum f/2.8 aperture, the sharpness of the lens is very similar at each like-for-like aperture across the entire focal length range.

The lens is tack sharp from centre to edges at f/4, f/5.6, f/8 and f/11. Detail is a fraction softer at f/2.8, although we would have no hesitation using the lens at its maximum aperture. If that maximum aperture is enough for your use, the 70-200mm is a bit like having four prime lenses in one. Peak sharpness at f/16 is similar to f/2.8. At f/22 diffraction adversely impacts image quality and it is the softest aperture.

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