Sigma's 18-35mm F1.8 DC HSM ($800) is a formidable piece of glass if you're looking for a medium focal length (short, if you're shooting full frame), wide aperture add-on for your DSLR, provided you've got the budget for an $800 lens.

Terrific image quality; Wide f/1.8 aperture; Snappy autofocus

Short zoom doesn't do much; May be overkill for APS-C users; Flaky lens cap

During Photokina in 2012, Sigma officially announced a re-structuring of their entire lens lineup, declaring that all future lenses would each be part of one of three new product lines: "Contemporary" for affordable consumer lenses, "Sport" for fast and weather-sealed telephoto lenses, or "Art" for...

Constant F1.8 aperture throughout zoom range; Excellent build quality throughout the lens' construction; Large focus and zoom rings are perfectly dampened and easy to find and grasp; Capable of shallow-depth of field wide angle portraits; The only fast and wide angle solution for Pentax's many...

Not weather-sealed despite excellent build quality and both internal zoom and focusing; Dreadful autofocus accuracy when using PDAF (looking through viewfinder; Bokeh can be jarring with highlights; producing "frog-egg" or "donut" ring bokeh; Stark color; temperature; and contrast shift from wide...

Prior to the introduction of the Sigma 18-35mm F1.8 DC HSM ($799 direct) lens shutterbugs with APS-C D-SLR cameras had to make a choice when it came to lens functionality. You can go with a zoom lens and cover a range of focal lengths, but even top-end models only opened up to f/2.8.

Sharp; Wide aperture; Reasonable price tag; Available for several camera systems

Big; No optical stabilization; Some wide-angle barrel distortion.

Ground-breaking f/1.8 maximum aperture wide-angle zoom for APS-C DSLRs gets a workout

f/1.8 maximum aperture; Excellent image quality; Full-time MF option; Very good sharpness

Not full-frame coverage; Somewhat weighty; Modest 2x zoom range

The word "groundbreaking" seems inadequate for describing the awesomeness of the Sigma 18-35mm f/1.8 DC HSM Art Lens. The primary reason for that awesomeness is the not-seen-in-any-other-zoom-lens f/1.8 aperture.

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.

The Sigma 18-35mm f/1.8 DC HSM lens is built for APS-C format cameras, providing a 27-52.5mm equivalent full frame field of view. At 1.78 lbs, the lens is not quite a bear; however, you'll definitely notice an increase and size and weight from other variable aperture zoom lenses built for APS-C...

When the announcement of Sigma's new 18–35mm lens arrived, some of our staffers chuckled upon opening the e-mail. Why? Because of what appeared to be a typo in the headline: Instead of f/2.8, it quoted f/1.8 as the maximum aperture!

Handling and features This much anticipated standard zoom lens for APS-C format cameras sports a fast f/1.8 maximum aperture throughout the zoom range and silent internal focusing with full time manual override.

The Sigma 18-35mm f/1.8 is a true game changer. I may not be a technical guru, but I love to snap pictures. I use my camera every day, and am always looking for new, incredible equipment that enhances my ability to capture a moment.