Sigma 24-70mm f/2.8 DG HSM ART OS - Review / Test Report - Sample Images & Verdict
Lens Reviews - Canon EOS (Full Format)

Sample Images

Click on an image for downloading the full-size variant.

MakeCanon
ModelCanon EOS 5DS R
ISO Speed200
Focal Length70.0mm
Aperture:f/2.8
Exposure1/800s

MakeCanon
ModelCanon EOS 5DS R
ISO Speed200
Focal Length70.0mm
Aperture:f/5.0
Exposure1/250s

MakeCanon
ModelCanon EOS 5DS R
ISO Speed200
Focal Length70.0mm
Aperture:f/2.8
Exposure1/1000s

MakeCanon
ModelCanon EOS 5DS R
ISO Speed200
Focal Length70.0mm
Aperture:f/2.8
Exposure1/640s

MakeCanon
ModelCanon EOS 5DS R
ISO Speed200
Focal Length24.0mm
Aperture:f/2.8
Exposure1/400s

MakeCanon
ModelCanon EOS 5DS R
ISO Speed200
Focal Length29.0mm
Aperture:f/10.0
Exposure1/200s

MakeCanon
ModelCanon EOS 5DS R
ISO Speed200
Focal Length29.0mm
Aperture:f/10.0
Exposure1/200s

MakeCanon
ModelCanon EOS 5DS R
ISO Speed200
Focal Length29.0mm
Aperture:f/10.0
Exposure1/320s

MakeCanon
ModelCanon EOS 5DS R
ISO Speed200
Focal Length24.0mm
Aperture:f/10.0
Exposure1/160s

MakeCanon
ModelCanon EOS 5DS R
ISO Speed640
Focal Length53.0mm
Aperture:f/2.8
Exposure1/25s

MakeCanon
ModelCanon EOS 5DS R
ISO Speed200
Focal Length70.0mm
Aperture:f/2.8
Exposure1/500s

Competition

You have quite a few lenses to chose from in the 24-70mm f/2.8 league. The Canon EF 24-70mm f/2.8 USM L II is certainly the preferred lens among professionals albeit, to be honest, we were actually not all that thrilled by its performance (either) and substantially more expensive than the 3rd party offerings. We reviewed the Tamron SP 24-70mm f/2.8 Di VC USD G2 (center) just a few days back. It is a solid performer but is suffering from a few shortcomings as well. It can't match the Sigma in the image center but it has a slight advantage regarding border/corner performance. The underdog in this range and the most affordable option is the Tokina AF 24-70mm f/2.8 AT-X PRO FX (left). Just like the Canon, this one comes without an image stabilizer. We'll have to review this one yet but based on the feedback out there it may well be the best of the non-OEM bunch ...

Visual comparison courtesy of camerasize.com.

Verdict

The Sigma 24-70mm f/2.8 DG HSM ART OS promised many things ... and delivered only a few of them. Let's start with a positive aspect - throughout the zoom range it is darn sharp in the broader image center. That's, of course, great when it comes to taking shallow depth-of-field images where your main subject stays within that zone. And the outer image is certainly very decent when stopping down a bit - that's except for the very long end. The border/corner performance is generally rather dismal at f/2.8 at all settings. Whether this is important in real life may be a different question but at the end of the day you are paying big bucks for having a f/2.8 lens. Lateral CAs are on the high side, especially in the image corners, so auto-correction during post-processing is a good idea. Both vignetting, as well as distortions, are typical for this lens class. The quality of the bokeh is comparatively good except in the foreground but that's usually of lesser concern.

There is one aspect where the Sigma lens excels - build quality. It is at least as good as on the Canon EF 24-70mm f/2.8 USM L II if not better. Sigma used top quality materials, it's tightly assembled as well as weather-proof. The AF is both fast and silent. The addition of an image stabilizer is certain a highlight albeit it isn't quite as efficient as the variant used by Tamron.

The test results show once more that this class of lenses (24-70mm f/2.8) is, at least to some degree, overrated. They may be relatively fast and expensive but, honestly speaking, they lack the greatness that should come with these price tags. And yes, that also applies to the Sigma 24-70mm f/2.8 DG HSM ART OS.

Optical Quality @ 50mp:    
★★★★★
Optical Quality @ 21mp:   
★★★★★
Mechanical Quality:
★★★★★
Price/Performance:
★★★★★

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