First, it’s important to consider that these lenses are very similar from a primary features perspective, with built-in stabilization being the most notable differentiator. With that in mind, let’s take a look at the shared set of features for these lenses:
Canon 24-70L II, Sigma 24-70 OS Art & Tamron 24-70mm VC G2 Shared Features
- Focal length range: 24-70mm
- Maximum aperture: f/2.8
- Filter size: 82mm
- Some degree of weather sealing
Now, let’s see how these 24-70mm lenses differ from a design perspective:
Canon 24-70L II, Sigma 24-70 OS Art & Tamron 24-70mm VC G2 Differences
|Canon EF 24-70mm f/2.8L II USM||3.48 x 4.45”
(88.5 x 113mm)
|Sigma 24-70mm f/2.8 DG OS HSM Art||3.46 x 4.24”
(88 x 107.6mm)
|Tamron 24-70mm f/2.8 Di VC USD G2||3.48 x 4.40”
(88.4 x 111.8mm)
1 FRR = Focus Ring Rotation
2 ZRR = Zoom Ring Rotation
When it comes to sharpness, it’s difficult to adequately describe which lens is the cream of the crop. The reason is simple – the “sharpest lens” title changes depending on the focal length and aperture chosen along with the specific area of the frame being considered.
After pouring over the results for quite some time, I decided to compile my own subjective findings. You can find them below. However, I encourage you to compare the lenses for yourself at the focal lengths and apertures you will likely use most to determine which lens may be sharpest for your specific intended uses.
For the results below, I ranked the three lenses at each specified focal length / aperture. If there was little or no discernible difference between two lenses, then I marked the comparison a tie.
As you can see, there isn’t necessarily a clear-cut winner from a sharpness standpoint when taking into consideration varying focal lengths, apertures and areas of the frame. However, note that the Canon EF 24-70mm f/2.8L II USM was either the highest ranked or tied for first in the center of the frame in every test.
Vignetting performance is not a significant differentiating factor for this group of 24-70mm f/2.8 lenses. There are minor differences, but… none that would likely motivate you to pick one over the other solely based on corner darkening. If precise vignetting performance is a priority for you, check out the links below.
Vignetting: Canon EF 24-70mm f/2.8L II USM vs. Sigma 24-70mm f/2.8 DG OS HSM Art
Vignetting: Canon EF 24-70mm f/2.8L II USM vs. Tamron 24-70mm f/2.8 Di VC USD G2
Vignetting: Sigma 24-70mm f/2.8 DG OS HSM Art vs. Tamron 24-70mm f/2.8 Di VC USD G2
When evaluating flare performance, I typically compare lenses at f/16 at their widest and longest focal lengths. These comparisons usually give me a good idea of what to expect from the lens in near worst-case scenarios. Keep in mind that one’s preference for tolerable types of flare is very subjective. Personally, I’d rather have an overall lose of contrast as opposed to clearly defined rings, circles and lines which are difficult to remove in post-processing and may block important details in the frame.
In this comparison, the Canon 24-70L II trails the Sigma and Tamron lenses at 24mm and f/16, at least as far as my personal preference is concerned.
Flare: Canon EF 24-70mm f/2.8L II USM vs. Sigma 24-70mm f/2.8 DG OS HSM Art
Flare: Canon EF 24-70mm f/2.8L II USM vs. Tamron 24-70mm f/2.8 Di VC USD G2
Between the Sigma Art and Tamron G2, the pattern of flare artifacts is very similar, although the Sigma may show a little more contrast.
Flare: Sigma 24-70mm f/2.8 DG OS HSM Art vs. Tamron 24-70mm f/2.8 Di VC USD G2
At 70mm, the Canon still shows more clearly defined flare artifacts while the other two lenses show less overall contrast. It’s difficult to pick a winner between the Sigma and Tamron lenses, but if pressed to pick one, I think I would prefer the Sigma’s results.
Zoom lenses typically exhibit barrel distortion at the wide end which transitions to pincushion distortion at the long end, and all of these lenses show these quintessential characteristics to varying degrees. As with vignetting, I don’t think there is enough difference among the lenses to regard distortion as a major differentiating factor. However, if minimal distortion is a priority for you, compare the lenses at your most-used focal length to see which one will work best for your needs.
Distortion: Canon EF 24-70mm f/2.8L II USM vs. Sigma 24-70mm f/2.8 DG OS HSM Art
Distortion: Canon EF 24-70mm f/2.8L II USM vs. Tamron 24-70mm f/2.8 Di VC USD G2
Distortion: Sigma 24-70mm f/2.8 DG OS HSM Art vs. Tamron 24-70mm f/2.8 Di VC USD G2
With image quality sufficiently covered, let’s dive into other aspects of the lenses to illuminate even more (likely more significant) differences.
Unlike most of the image quality comparisons above, this comparison is very straightforward – the Canon 24-70L II doesn’t have built-in stabilization, while the Sigma and the Tamron lenses do. Between the two, the Sigma 24-70 Art seemed to provide slightly more handheld assistance in our tests.
Before we move on, I should point out that stabilization can have a huge impact on image quality, as a lens can only achieve its highest image quality when camera shake is neutralized (either by the use of a fast shutter speed or by lens/camera stabilization). Of course, stabilization does not help if your subject is moving, but… it can help a great deal when photographing stationary subjects.
Generally speaking, you’ll get the best AF performance – especially in regards to accuracy and consistency – when using Canon lenses with Canon cameras. In the case of the Canon 24-70L II, Sigma 24-70 OS Art and Tamron 24-70 VC G2, while the third party lens manufacturers have certainly closed the performance gap over the past few years, the general rule still applies.
The good news is that all of the lenses perform quite well when using the center AF point, assuming a proper autofocus microadjustment (AFMA) calibration. Unfortunately, AF performance degrades noticeably while utilizing the outer AF points with both the Sigma Art and Tamron G2 lenses. Our testing indicates that the Sigma is a little more consistent than the Tamron with outer AF point use.
Those who don’t mind employing a focus-and-recompose technique or otherwise can utilize Live View focusing for image capture, can maximize their in-focus take home percentage when using third-party lenses.
One area where the third-party lenses are advantaged is autofocus calibration through the use of Sigma’s USB Dock and Tamron’s TAP-in Console. While many high-end Canon DSLRs have the ability to fine tune AF using AFMA, most consumer-to-mid-level Canon DSLRs do not have this feature. And even if your camera does feature AFMA, the USB Dock and TAP-in Console allow for finer control of adjustment options (including separate adjustments for varying focus distances). Another benefit of dock-adjusted AF is that a lens can be calibrated once for use on several bodies (assuming the same adjustment is necessary throughout the set) instead of having to enter the same adjustment value in-camera on several bodies.
Price is one lens aspect that is quite easy and straightforward to compare. The Canon 24-70L II is the most expensive lens of the bunch, with the Sigma’s price being about 30% lower than the Canon’s (current MSRP in North America, no rebates). The Tamron is priced slightly less than the Sigma.
One thing to keep in mind when choosing to invest in a lens is the brand’s typical resale value. Of the three manufacturers, Canon lenses tend to hold their value better than the third-party options.
By not including image stabilization in the EF 24-70mm f/2.8L II USM lens, Canon left the door wide open for third-party manufacturers to produce an even more versatile and/or enticing general purpose lens. Both Sigma and Tamron saw the crack in Canon’s armor, and the introduction of the 24-70mm f/2.8 DG OS HSM Art and 24-70mm f/2.8 Di VC USD G2 lenses represent the culmination of those manufacturers’ efforts to unseat Canon in the professional general purpose lens market by taking advantage of Canon’s biggest shortcoming.
Has either brand succeeded? In some ways the answer is “yes,” and in other ways, “no.” None of the lenses in this comparison blew away the competition, with the “best lens” being different based on one’s own personal preferences and requirements. For those that cannot afford to miss a shot and prefer using viewfinder AF along with outer AF points (think, wedding photographers), the Canon EF 24-70mm f/2.8L II USM will likely be best. For the ultimate in versatility, however – thanks in large part to in-lens stabilization – the Sigma 24-70mm f/2.8 DG OS HSM Art and Tamron 24-70mm f/2.8 Di VC USD G2 both offer compelling performance at a more budget friendly price. Ultimately, the choice between the Sigma and Tamron will likely hinge on one’s preference for more accurate AF (Sigma) or increased potential sharpness (Tamron).
Want to know more about these lenses? Check out our full reviews linked below.
- Canon EF 24-70mm f/2.8L II USM Lens Review
- Sigma 24-70mm f/2.8 DG OS HSM Art Lens Review
- Tamron 24-70mm f/2.8 Di VC USD G2 Lens Review
Canon EF 24-70mm f/2.8L II USM Lens
B&H | Amazon | Adorama | Canon USA Store | BuyDig | Wex Photographic | Henry’s
Sigma 24-70mm f/2.8 DG OS HSM Art Lens
B&H | Amazon | Adorama | BuyDig | Wex Photographic | Henry’s
Tamron 24-70mm f/2.8 Di VC USD G2 Lens
B&H | Amazon | Adorama | BuyDig | Wex Photographic | Henry’s