Lens Reviews

Sigma’s 18-35mm f/1.8 DC HSM is part of their DC series of lenses designed for APS-C-sized sensors so the imaging circle is matched to the size of the sensor. For this assignment, I used a Canon EOS 60D with a 22.3x14.9mm sensor, producing an equivalent angle of view of a 28-56mm lens. Shooters of Nikon, Pentax, Sigma, and Sony cameras, the other mounts for which the lens is available, will achieve an angle of view equivalent to 27-52mm. Unlike other lens manufacturers, Sigma priced the different mounts the same ($799) so don’t feel you’re going to be paying a premium for your camera choice. Bucking a trend with camera manufacturers’ lenses, the Sigma 18-35mm f/1.8 DC HSM includes a lens hood at no extra charge.

A tilt-shift lens can be thought of as a flexible visual tool in the many ways it allows you to image the world. Unlike a standard lens, even a zoom, with a set point of view enforced by stance, elevation, focal length, and, within certain limits, depth of field, the tilt-shift lens opens visual doors a “fixed” lens will not. By tilting the lens within the mount you can enhance or greatly diminish depth of field beyond the “normal” abilities of the focal length and aperture setting. By shifting the lens you can “fix” perspective distortion or exaggerate it for “trick” effects.

Lensbaby Spark lets your camera color outside the lines. It mounts directly on your Canon or Nikon and focuses manually when you squeeze it toward the rear while watching the sharp, sweet spot move around in the viewfinder. The affordable Lensbaby Spark deserves a spot on every photographer’s holiday wish list.

While the Sigma 150mm f/2.8 lens has been out for a good while we decided to take a closer look at one of the most interesting pro-oriented products in their lineup. One of the key selling points in this lens is built-in optical image stabilization (“OS” in Sigma-speak) to aid in achieving camera-shake-free, handheld exposures. Granted, image stabilization in a macro lens is not the be-all and end-all of successful close-ups, though it sure gives added insurance. And because the Sigma 150mm OS macro is optimized for full-frame D-SLRs, it allows for use at the stated focal length with such cameras and provides even greater effective focal length with APS-C-type SLRs.

There’s something about a fixed focal length lens that brings the photographer out in me. It forces me to move in and back from compositions without resorting to a zoom. Yes, there are times when a zoom is most appreciated—especially the fast constant aperture zooms now available—but a prime puts me in a mindset that a zoom has yet to match.

The difference between a “constant” aperture zoom and other standard zooms is that when you increase the focal length on the standard zoom the maximum aperture narrows. This might make the difference between being able to hand hold or not when zooming in, and may indeed force the use of higher ISOs. Known as “fast” lenses, constant aperture zooms are pricier and bulkier than their variable-aperture counterparts. And to sweeten the pot, we’ve seen more and more fast lenses with built-in image stabilization, which gets you even more low light and steady shot capability.

The Sigma 85mm f/1.4 EX DG HSM lens (average price: $969 on various Internet sites) is designed for full-frame cameras; with an APS-C multiply by your usual factor. At about 25 oz, I’d describe the lens as substantial, but not hefty. One of the reasons for the weight is the build—11 elements in eight groups, including the use of SLD glass, Sigma speak for Special Low Dispersion. The big chunk of glass on the end requires a 77mm filter. As to handling, Sigma has gone from their black “crinkle” finish to a smooth black rubberized finish that feels great to the touch. It’s plastic, not metal, but based on my experience with previous Sigma lenses, I’ve found them to be built to professional standards and can take a lot of abuse.