All About Photographic Lenses.
Specifications, comparison, reviews, MTF-charts for lenses by Canon, Nikon, Sony, Pentax, Olympus, Sigma, Tamron, Carl Zeiss, etc.

Sigma DG 50-500 mm f/ 4.5-6.3 APO OS HSM used:

NameFull namePlaceScoresRank
1Michael Ransby 219.5lvl.2 (Lens-Adept)