Pour ceux que ça intéresse, un test tout frai sur les 24 Mpx du D3X et sur le D200 :
http://www.lenstip.com/172.1-Lens_review-Sigma_24-70_mm_f_2.8_EX_DG_HSM_Introduction.htmlConclusion
Pros:
* a very solid barrel but, in the same time, lighter and smaller than the barrels of its rivals,
* fabulous frame centre picture quality,
* very good frame edge picture quality on the APS-C/DX matrix,
* good frame edge picture quality on the full frame matrix on stopping down by 1 EV,
* good chromatic aberration correction on the edge of the APS-C/DX matrix,
* slight astigmatism,
* slight coma in the small matrix corners,
* practically no vignetting on the APS-C/DX matrix,
* autofocus silent and quick,
* very good transmission,
* good quality/price ratio,
* a warranty three years long with the possibility of extending it by two more year,
* generous selection of accessories.
Cons:
* too low picture quality in the full frame corner near the maximum relative aperture,
* visible distortion at wide apertures, especially on the full frame,
* significant vignetting toward the focal length ends,
* quite visible coma in the full frame corners for the range of 24-45 mm.
Sigma is known for launching lenses with good quality/price ratios. In most cases they are only slightly worse than the brand-name competitors (if at all) but they are significantly cheaper. The new Sigma 24-70 mm f/2.8 fits this strategy requirements very well. It is two times cheaper than the similar Canon, Nikon or Sony/Zeiss lenses but it is their equal (even more than equal in the case of the Canon) when it comes to optical properties. In the same time, it weights less and it is smaller and its warranty period is impressive. I think that the new Sigma 24-70 mm will find a lot of satisfied users as they will be able to take pictures of similar in quality to those, taken with more expensive, brand-name lenses.
Pas mal
