Following on the heels of the popular new 35mm f/1.4 “Art” series lens, Sigma has announced the world’s first zoom lens with an f/1.8 aperture available throughout the entire zoom range: the 18-35mm f/1.8 DC HSM “Art” series lens for APS-C sensor cameras.
Far from being “just another zoom lens”, Sigma’s new lens is truly innovative. When I first heard rumors about the lens, in fact, I suspected that it was a hoax. Currently, the best professional lenses offer an f/2.8 aperture throughout the zoom range. The 18-35mm f/1.8 provides more than twice as much light throughout the range, a full 1 and 1/3 f-stops. Typical consumer lenses are usually variable, with a moderately large aperture like f/3.5 available at the wide angle end of the range, but with a much smaller aperture, like f/5.6, available at the opposite end of the range. An f/5.6 aperture lets in less than 1/8th the amount of light that an f/1.8 does.
Beyond the large aperture, the lens’ characteristics are not especially exciting. The lens has a beautiful finish, and as a member of the “Art” series, should be sturdy and well designed. The lens contains 17 elements in 12 groups, including multiple “SLD” glass elements and special coatings to reduce aberrations. For smoother bokeh, the lens uses 9 blades designed to provide a nearly circular aperture. It is worth noting, perhaps, that the minimum aperture of the lens is f/16, where f/22 or f/32 is much more common.
Of course, Sigma’s optics will have to be up to the job to make this a truly great lens. If it turns out that the image quality is very poor at f/1.8 or f/2, we’ll be able to write the lens off as an great marketing scheme. I’m looking forward to getting my hands on one for some serious testing.
There are currently no estimates for prices or availability, but it is now clear that the Sigma 35mm f/1.4 was no fluke; the Sigma corporation is now striving for excellence and innovation, and it appears to be producing results unmatched by Canon or Nikon. Good show, Sigma!
