| Sigma 24-70mm f/2.8 EX Specifications | |
| Frame Coverage | 35mm |
| Lens Construction (groups) | 13 |
| Lens Construction (elements) | 14 |
| No. of Diaphragm Blades | 9 |
| Minimum Aperture | 32 |
| Closest Focusing Distance | 0.4m (15.7") |
| Maximum Magnifcation | 0.26x |
| Filter Diameter | 82mm |
| Maximum Diameter x Length | 88.7mm x 115.5mm (3.5" x 4.5") |
| Weight | 715g (25.2oz) |
Reviews
Source
SailbyAir.com
Both lenses have their advantages, Sigma's mainly being price. The advantages need to be carefully weighed against their cost. I believe the Canon lens is the superior lens in practically all respects from image quality to build quality and features. That said, the Canon L lens costs three times as much as the affordable Sigma lens. As the aperture goes up, the differences between the two will go down.
PhotoZone.de
The Sigma AF 24-70mm f/2.8 EX DG macro showed an impressive performance throughout all characteristics. It is a very sharp lens at all mainstream aperture settings. Distortions, CAs as well as vignetting are moderate and usually nothing to worry about. The build quality is very fine and the AF is pretty fast despite the enormous glass elements and a conventional AF micro-motor.
Photodo.com
This is a large lens that is well built and feels like it will go the distance. The zoom ring is surprisingly small for the size of the mechanism it has to move, but although a little heavy in operation, worked well. Autofocus is noisy but accurate. The 24mm end is just wide enough to start being call wide angle on a cropped sensor, but if you are still mixing digital with film, then this lens is a very good buy.
The-Digital-Picture.com
If the prices were the same, I don't think anyone would choose the Sigma 24-70mm f/2.8 EX DG Lens over the Canon EF 24-70mm f/2.8 L USM Lens. But, the Sigma is less than half the price of the Canon. And for that reason, many people are willing to overlook the physical and optical quality differences between these two lenses.
