Sigma 18-35mm f/1.8 Review: The Best Low-Light Zoom Lens By a Mile
What Is it?
An $800 wide-to-medium angle zoom lens for Canon,
Why Does It Matter?
It's got an aperture at f/1.8, a spec previously found only in prime lenses and unusually wide for a zoom. That means the lens is more sensitive to low light than most high-end zooms, which top-out at f/2.8.
Sigma did an outstanding job making a sleek, solid-feeling lens with great tactility. It uses a material called Thermally Stable Composite, which has a feel that combines the TK of metal and the TK of plastic, with a nice matte finish. The rubber zoom and focus rings are nice and wide, with great resistance. Even the lens cap is well-designed with a rim that lies flush with the lens, and a pinch fastener that isn't a fuss.
In the context of zoom lenses, the Sigma 18-35mm is a pleasure to use. It's a tad on
Wide-open at f/1.8 (click to download full-size image)
Stopped down to f/5.6 ( click to download full-size image )
The comfort of being able to open up that aperture in low light is priceless. The biggest surprise is the performance. You might expect a headline feature like f/1.8 aperture to necessitate certain sacrifices. It doesn't, at least not when it comes to image quality.
In an ideal world, this lens would offer a little more scope at the wide end. 18mm is the full-frame equivalent of about 29mm on a 1.6x crop sensor. That's acceptable, but not fantastic if you are going for really wide shots.
The Best Part
You no longer have to sacrifice aperture size when shopping for a zoom lens. If you are a photojournalist, concert, or documentary shooter with a cropped sensor DSLR, this lens is a godsend.
There's no image stabilization. That one feature would have skyrocketed this lens into must-have territory for video shooters especially. It would also meant a much higher price, though.
This Is Weird
We did notice a decent amount of purple fringing around highlights. This is very easily fixed automatically in Lightroom or Photoshop, so we don't consider it a major flaw.
- We shot with the lens on a Canon 7D.
- We directly compared shots with a Canon 24-105 f/4. In terms of sharpness, the two lenses were nearly identical.
- If you are used to a zoom with image stabilization, you might want to bump the shutter speed up on the Sigma a bit more than you are used to in order to prevent shaky images.
- Sigma says a Pentax mount version is in the works. We would love to see versions of this lens for mirrorless systems as well, such as an Sony E-mount or micro-four-thirds mount version.
Should You Buy It?
In almost all cases, if you have regular need for a serious zoom lens, then yes. Unless you have a niche concern like image stabilization for video, or need a longer focal range, the Sigma is a great replacement for your current walk-around zoom. The price is an extremely reasonable $800 , and there is currently no lens out there quite like it.