Introduced in 2002 as the successor to the 28-70mm f/2.8, the first generation EF 24-70mm f/2.8L proved itself a very capable performer. Comparing the performance side-by-side the two share similar scores for distortion, vignetting and chromatic aberration (in fact the older lens was measured with slightly lower levels, though it’s unlikely to be noticeable in real-world use), however, significant advances have been made in sharpness (equating to a 33-percent improvement overall) and transmission values, down from T3.4 to T3.0.
Both lenses are sharp in the centre but the improvement in the sharpness across the field accounts for the dramatic improvement. We’re also used to seeing the performance drop significantly at longer focal lengths, and, while it’s not quite at the same quality levels as the shorter lengths, it’s still noticeably better than the previous model.
Comparing the Field Maps at 35mm f/2.8, the Mk II (left) shows excellent uniformity. Although acutance is 8% percent higher in the centre, the corners aren’t far behind at 5%
Zooming out a little to 50mm (again at maximum aperture) and the Mk II still shows a 5.5% improvement in acutance in the centre and 4% in the corner, although to be fair the older lens holds up well.
At the longest focal length (70mm) and maintaining the f/2.8 maximum aperture setting, the shortcomings of the older version can be seen quite clearly. Direct comparisons reveal a 7.3% higher acutance in the center of the field, while the corner is an impressive 11% percent higher with the new lens over the first-gen model.
As for transmission, the new lens is noticeable faster with a maximum of T3.0 and more closely resembles the f/2.8 theoretical aperture value. The graphs above reveal the relative differences between the two quite clearly (the red line plotting the results of the new lens, against the blue for the original version). Both lenses have the vaunted f/2.8 maximum aperture but our measurements reveal the new version is faster (brighter) by nearly a one ½ stop at 24mm dropping to just less than a one 1/3 stop brighter at 70mm.
As a Canon user, potential purchasers of this lens will also likely consider the firm’s popular EF 24-105mm f/4L. Both are L-series and targeting professional photographers, however while the 24-70mm f/2.8 is one stop faster (theoretically), the 24-105mm f/4 has extra flexibility for portraits with the popular 85-105mm focal lengths, boasts image stabilization and at around $1000 less, is significantly more accessible in price.
Not only does the EF 24-70mm f/2.8L II USM compare well against its predecessor, it also outperforms the 24-105mm f/4L in most areas when tested on the Canon EOS-1Ds MkIII. Not only is it significantly sharper and almost 1 2/3 stops faster, it has noticeable less distortion. However, not to be outdone, the 24-105mm f/4L has slightly less vignetting while also boasting quite low levels of chromatic aberration.
DxOMark Score Map:
A careful look at the DxO Mark Score Maps reveals the 24-70mm f/2.8 II USM to be a better performer optically than the 24-105mm f/4 at every aperture and focal length combination. However, in fairness, the performance of 24-105mm f/4 tails off more noticeably past the 70mm limit of the 24-70mm f/2.8 lens. If we compare the same focal range (as we should), the new lens outperforms the 24-105mm between the crucial f/4 and f/8 range but it also performs very well at f/2.8.
Map Sharpness at 50mm f/4 focal length:
If we take a closer look at the sharpness map for both lenses at a focal length of 50mm and at a comparable aperture (f/4 in this instance) we can begin to see the difference. Although one stop down from the maximum aperture, which is an advantage with most lenses, the new EF 24-70mm f/2.8L II USM delivers very good sharpness in the centre and that holds up well across the field into the corners. In contrast, the EF 24-105mm f/4L IS USM can only just about match the new lens in the centre, with the image noticeably softening towards the edges and corners. While this isn’t surprising given the fact lens performance is weakest wide-open, the results reflect the limited aperture choices and, therefore, typical use for photographers working in available light.
Although the new EF 24-70mm f/2.8L II has two UD (ultra low dispersion) and one Super UD glass elements in the optical construction, in our global map the 24-70mm f2.8 has traces at every aperture and every focal length (though, unsurprisingly, it’s strongest at the faster apertures and wider end). By comparison, the simpler EF 24-105mm f/4L has much lower levels, and is only an issue at the wider end at the maximum aperture.
If we examine the field map of the two lenses, we can see the lateral chromatic aberration actually doesn’t look quite as problematic as it it’s portrayed in the global map (above). Fortunately, lateral chromatic aberration is simple to remove in software (such as DxO’s own Optics Pro image workflow solution).
Canon vs Nikon vs Sony (Zeiss): the Flagship midrange contest
While the Canon version is the latest to market, both Nikon and Sony users can call on relatively new designs. The Sony made Zeiss designed model is the oldest of the three and yet it has some very good scores, with each either bettering or matching the newer Nikon AF-S 24-70mm f/2.8 and, at first sight, rivaling the new Canon optic. While the Sony has slightly lower Distortion (at 0.3%) and Vignetting (at -1.4 EVs) than the Canon, the overall DxOMark scores of 26 vs 21 respectively are mainly influenced by the Canon’s uniform sharpness over the image field. This is noticeable at the wider apertures throughout the zoom range, and particularly at the longer focal lengths. The Canon also edges ahead with the impressive Transmission score.