Available for Sigma, Nikon and Canon (the version tested) DSLR cameras, the Sigma 70-200mm f/2.8 DG OS HSM Sports lens delivers what most photographers need in a telephoto lens, especially with its constant large aperture of f/2.8 throughout its focal range.
It features a dust-and splash-proof structure consisting of a magnesium-alloy barrel and a coated brass mounting. Its front and rear lens elements are said to have water-and oil-repellent coatings for increased protection.
The lens' build is sturdy, giving users plenty of confidence when handling it. While I did not dunk it in water or throw sand at it, it did get caught in a bout of torrential rain during the review and came through unscathed.
The lens has 24 glass elements - including 10 low-dispersion glasses - arranged in 22 groups with 11 rounded aperture blades.
On the outside, the lens has two control rings - one for zooming and the other for focusing.
I am a tad perplexed by their positioning though, as the zoom ring is close to the front of the lens while the focusing ring is in the mid-section.
Zoom rings are usually placed at the mid-section of lenses for better centre of gravity when holding the lens. While this is not a deal-breaker, it is certainly something you will need to get used to.
There are three Focus Hold buttons positioned between the two control rings, around the circumference of the barrel. On the left side of the barrel are four switches for changing from autofocusing (AF) to manual focusing mode, limiting the focusing distance, toggling through image-stabilisation modes and selecting custom functions.
PRICE: $2,088 (Sigma-mount; Nikon-mount; Canon-mount, version tested)
FOCAL LENGTH: 70mm to 200mm
MAXIMUM APERTURE: f/2.8
MINIMUM APERTURE: f/22
MINIMUM FOCUSING DISTANCE: 120cm
VALUE FOR MONEY: 4/5
For this review, I used the lens with my trusty Canon EOS 7D.
The AF performance was superb, with almost-instant focus lock under bright sunlight. Even under dim lighting conditions, focus lock took at most one second.
The performance of the optics is equally stellar. Images shot using this lens generally looked sharp with minimal image distortion and negligible chromatic aberration throughout its entire focal range.
At the 70mm focal length, edge-to-edge sharpness was outstanding from f/2.8 to f/11. Only at f/16 did the edge sharpness decline slightly, but the centre sharpness was consistent through the aperture range.
From 100mm onwards, I saw some edge softness from f/2.8 to f/5.6. It was only at f/11 that the edge sharpness improves to become comparable with what I saw at 70mm.
Centre sharpness was great from 100mm onwards and across all aperture sizes, albeit not as sharp as at 70mm.
In terms of pricing, the Sigma lens is much more competitive compared with the equivalent original DSLR camera lenses. For example, the latest Canon EF 70-200mm f/2.8L IS II USM telephoto lens is priced at $3,499, about $1,400 more than the Sigma.
The only downer is that the Sigma lens is slightly heavier by 320g compared with the original Canon telephoto lens mentioned. Guess that is the price to pay for its sturdiness.
• Verdict: For those looking for a fast telephoto lens, you will not go wrong with the Sigma 70-200mm f/2.8 DG OS HSM Sports.