Sigma AF 24-70mm f/2.8 EX DG HSM (DX) - Review / Test Report
Lens Reviews - Nikon / Nikkor (APS-C)

Review by Markus Stamm, published December 2009

Introduction

A 24-70/2.8 is one of the key lenses for many professional photographers and consequently such a lens is currently offered by all three manufacturers that also offer full frame DSLR cameras. Unfortunately these lenses are out of reach for many amateurs price wise.

The only third party company confident enough to offer a lower cost alternative solution was and still is Sigma, who overhauled the 24-70/2.8 EX lens and as one of the main new features added a HSM drive (finally!). The non-HSM lens remains in Sigma's portfolio, at least for now.

While these fast standard zooms are primarily targeted at full frame cameras, they are also very popular among users of APS-C camera. Consequently, we'll have a look at how the lens performs on our DX test cameras, the Nikon D200, where its field of view resembles a 36-105mm lens on a full frame camera. For obvious reasons, parts of the FX review are reused here.

Unlike the Nikkor 24-70, the Canon 24-70L and its older non-HSM sister the Sigma HSM lens is a more "traditional" zoom lens, shortest at its 24mm setting with one inner lens tube extending towards the tele end. At least at its wide angle setting the lens feels way more compact than the Canon and Nikon lenses with their huge hoods, but noticeably thicker.

The build quality is excellent, zoom and focus ring are damped and operate smoothly, there's no wobbling and the lens features the well known EX crinkle finish. It is not dust or weather sealed, though. The tested sample showed no signs of zoom creeping.

Zoom and focus ring work in "Canon style" which is the opposite direction of Nikkor lenses. Someone using mainly Nikon glass might need some time to get used to it and override his or her muscle memory. This is of course no issue with the EF-mount version of the Sigma lens, any Canon shooter should feel right at home here.

Thanks to an IF (internal focusing) design the front element does not rotate so using a polarizer is no problem. However, because of a fairly large filter diameter (82 mm) which this lens inherits from its predecessor, a polarizer, especially a higher quality one, easily becomes a rather expensive accessory. Like all Sigma HSM lenses the 24-70 EX features a silent-wave (ultrasonic) AF motor providing extremely fast and near-silent AF operations and manual focus override at any time. Like most modern F-mount lenses it does not feature an aperture ring (a G-type lens).

Specifications
Equiv. focal length36-105 mm (full format equivalent)
Equiv. aperturef/4.2 (full format equivalent, in terms of depth-of-field)
Optical construction14 elements in 12 groups inc. 3 ELD, 2 SLD and 3 aspherical elements
Number of aperture blades9 (rounded)
min. focus distance0.38 m (max. magnification ratio 1:5.3)
Dimensions88.6 x 94.7 mm
Weight790 g
Filter size82 mm (non-rotating)
Hoodbayonet mount, supplied, petal-shaped
Other featuresHSM ultrasonic drive, padded lens pouch included