![](/images/perpan/7.jpg)
Sigma 100-400mm f/5-6.3 DG OS HSM Contemporary Review
The Sigma 100-400mm F/5-6.3 DG OS HSM C is a well-made lens, with an optical design of 21 elements in 15 groups. Four of those are SLD (Special Low Dispersion) elements to help increase contrast and sharpness while minimizing color fringing. The lens relies on Sigma's ring-type HSM (Hyper Sonic Motor), which has been a mainstay on the company ...