By Diane Berkenfeld
The Sigma Corporation of America released the Sigma 10-20mm F/3.5 EX DC HSM lens earlier this year. The lens has a maximum aperture of f/3.5 throughout the entire zoom range, and minimum aperture of f/22. Sigma offers the lens in mounts for Sigma, Nikon, Canon, Sony and Pentax DSLRs that utilize an APS-C sized image sensor. What that means is, if you’ve got a DSLR with a full frame image sensor, or use the lens on a film SLR, you’re going to see vignetting in the image.
The Sigma 10-20mm F/3.5 EX DC HSM is made up of two ELD (Extraordinary Low Dispersion) glass elements and a SLD (Special Low Dispersion) glass element for correction of color aberration; four aspherical lenses provide correction for distortion and allow for a compact lens. A Super Multi-Layer coating reduces flare and ghosting. The lens also utilizes a Hyper-Sonic Motor for fast and quiet auto-focusing. You can also manually focus the lens if you’d like. Pentax users: Sigma notes that Pentax camera bodies that don’t support HSM will not be able to auto-focus this lens.
The lens offers a super-wide angle view of 102.4 degrees at 10mm and 63.8 degrees at 20mm. Place your subject(s) close to the edges and you’ll get an exaggerated perspective; center your subject(s) for minimal distortion. Sigma ships the lens with a nice padded case with a zipper closure, and a petal-type lens hood. The lens will take 82mm filters. At 18.3 ounces, the 10-20mm lens is pretty light.
I tested out the Sigma 10-20mm F/3.5 EX DC HSM lens with a Nikon D100 DSLR, which utilizes the DX image sensor. With the DX image sensor, which has a 1.5x magnification factor, the zoom range of the lens is equivalent to a 15mm – 30mm lens on a 35mm camera. One subject the lens is great for, is street photography. I used to shoot such photojournalistic style images with a 24mm prime lens on a Nikon F3 film SLR and loved the wide view I had.
There are some folks who feel you can’t get high quality lenses from third party manufacturers, but this Sigma lens throws that argument out the window. The lens is bright and clear, and sharp. The minimum focusing distance of the lens is 9.4-inches throughout the entire zoom range. This is such a great feature, because once you’re at your minimum focusing distance, you know you can zoom in or out if need be and not have to move the camera to keep focused on your subject. I really liked the Sigma 10-20mm F/3.5 EX DC HSM lens. It offers great quality for the price.
The street price of the Sigma 10-20mm F/3.5 EX DC HSM is $649.99. For more information, check out the website at www.sigmaphoto.com.