On Fri, 19 Jun 2020 13:13:19 +0200, Paul Carmichael
wrote:

The Sigma 120-400mm 5.6 is the only tele/autofocus that I have. My other lenses are mostly
Samyang primes.

FYI, Review of the lens at imaging-resource.com
https://www.imaging-resource.com/len...sm-apo/review/

Sharpness
The 120-400mm is a fairly sharp lens, but its performance is optimized
for the wider range of its focal length spectrum. As you zoom in
towards the 400mm range, image sharpness degrades significantly.