Introduction

Ease of Use

Weighing in at 810 grams and measuring 12cm in length, the Sigma 18-35mm F1.8 DC HSM is a big lens given its modest focal length. As seen in the photos below, it complements a camera like the Canon EOS 700D / Rebel T5i very well.

The Sigma 18-35mm F1.8 DC HSM lens mounted on a Canon EOS 700D

The Sigma 18-35mm F1.8 DC HSM lens mounted on a Canon EOS 700D

The Sigma 18-35mm F1.8 DC HSM lens mounted on a Canon EOS 700D

Build quality is excellent given the relatively affordable price tag. The lens has a plastic shell with a mixture of metallic parts and a new compound material, TSC (Thermally Stable Composite), used inside. It also incorporates a brass bayonet mount that's supposed to be more durable. The optical elements are made of high-grade glass. The focus ring is pleasingly wide and ridged for easier grip.

Side of the Sigma 18-35mm F1.8 DC HSM lens

Side of the Sigma 18-35mm F1.8 DC HSM lens

Top of the Sigma 18-35mm F1.8 DC HSM lens

Bottom of the Sigma 18-35mm F1.8 DC HSM lens

In terms of features, the Sigma 18-35mm F1.8 DC HSM offers all the basics that you need from a standard zoom lens. The main exception is the lack of built-in Vibration Reduction, although the very fast maximum aperture of f/1.8 makes up for this.

Side of the Sigma 18-35mm F1.8 DC HSM lens

Side of the Sigma 18-35mm F1.8 DC HSM lens

Focusing is usefully internal and manual focusing is possible when set via the Focus switch on the lens barrel. Full-time manual focus override is also available at any time simply by rotating the focus ring. The lens doesn't change in length when zooming from 18mm to 35mm.

A clear distance scale in both feet and meters runs from the closest focusing distance of 0.28m / 0.92 ft to infinity.

Front of the Sigma 18-35mm F1.8 DC HSM lens

Rear of the Sigma 18-35mm F1.8 DC HSM lens

Front of the Sigma 18-35mm F1.8 DC HSM lens

Rear of the Sigma 18-35mm F1.8 DC HSM lens

Surprisingly given its price, the Sigma 18-35mm F1.8 DC HSM ships with a good quality soft case and also a plastic petal-shaped lens hood. It accepts 72mm filters.

The Sigma 18-35mm F1.8 DC HSM lens in-hand

Front of the Sigma 18-35mm F1.8 DC HSM lens, with the supplied LH780-06 lens hood fitted

Focal Range

At the 18mm focal length the angle of view is 76.5 degrees.

 Field of view at 18mm

At the 35mm focal length the angle of view is 44.2 degrees.

 Field of view at 35mm

Focusing

The Sigma 18-35mm F1.8 DC HSM lens has a wide focus ring. There are hard stops at both ends of the range, making it easier to set focus at infinity. Polariser users should be pleased that the 72mm filter thread doesn't rotate on focus.

When it comes to auto-focusing, the Sigma 18-35mm F1.8 DC HSM zoom is a quick performer, taking about 0.15 seconds to lock onto the subject when mounted on the Canon EOS 700D that we tested it with.

We didn't experience much "hunting", either in good or bad light, with the lens accurately focusing almost all of the time. It's also a very quiet performer, thanks to the built-in HSM (Hyper Sonic Motor), which makes this lens well-suited to video recording.

Chromatic Aberrations

Chromatic aberrations, typically seen as purple or blue fringes along contrasty edges, can be detected in some shots, but they are not very prominent at all.

Vignetting / Light Fall-off

With the lens set to its maximum aperture of F1.8, there is significant light fall-off in the corners at both ends of the zoom range. Stopping-down to F4 virtually eliminates this. There is also some modest barrel distortion at the 18mm focal length.

Vignetting at 18mm

Vignetting at 35mm

Macro

The Sigma 18-35mm F1.8 DC HSM isn't claimed to be a macro lens, but it delivers good performance nonetheless. It has a minimum focusing distance of 28cm/11.0in and a maximum magnification ratio of 1:4.3. The following example demonstrates how close you can get to your subject, in this case a Compact Flash memory card.

Close-up performance

Bokeh

Bokeh is a word used for the out-of-focus areas of a photograph, and is usually described in qualitative terms, such as smooth / creamy / harsh etc. In the Sigma 18-35mm F1.8 DC HSM lens, Sigma employed an iris diaphragm with nine rounded blades, which has resulted in very nice bokeh in our view. We do realise, however, that bokeh evaluation is subjective, so we've included several 100% crops for your perusal.

Sharpness

In order to show you how sharp this lens is, we are providing 100% crops on the following pages.