Sigma DG 634101 28-70mm

The Sigma 28-70mm f/2.8-4 DG Aspherical is a featherweight full-frame zoom for Canon EF with a genuinely fast f/2.8 aperture at the wide end and lovely bokeh. But it's an older design with no stabilization, no weather sealing, and mediocre autofocus. At $823 USD, it's a tough sell unless you specifically need that bright wide end in a tiny package. A used copy at a lower price makes a lot more sense.

The headline number is that f/2.8 aperture at 28mm, which ranks in the 88th percentile across all lenses in our database. That's genuinely impressive for a lens this small and this affordable. You're getting real low-light capability and real subject separation at the wide end, which is not something you can say about most compact zooms. The bokeh quality also ranks in the 86th percentile, which means the out-of-focus rendering is smooth and pleasant rather than busy or harsh. For portraits, that's a big deal.

But the aperture is variable, dropping to f/4 by the time you hit 70mm. That's the trade-off for the compact size. At 70mm and f/4, you're getting roughly half the light of a constant f/2.8 zoom, which means higher ISOs or slower shutter speeds in dim conditions. The optical quality overall sits right at the 49th percentile, so sharpness and contrast are about average for this class. The aspherical element helps control distortion and spherical aberration, and the multilayer coating does a decent job suppressing flare, but this isn't a lens that's going to wow you with corner-to-corner sharpness wide open.

The Tamron 18-300mm f/3.5-6.3 Di III-A VC VXD is the obvious modern alternative if you're willing to trade aperture for reach and stabilization. That Tamron covers an enormous focal range and includes vibration compensation, but it starts at f/3.5 and gets slow quickly. The Sigma's f/2.8 at 28mm is a completely different shooting experience in low light. The Sony E 18-135mm f/3.5-5.6 OSS is another stabilized option with more reach, but again, you're giving up that bright wide end.

The Panasonic Leica DG Vario-Elmarit 12-35mm f/2.8 is a constant aperture zoom that beats the Sigma on consistency, but it's designed for Micro Four Thirds, not full-frame Canon EF. And the Meike 85mm f/1.4 II is a prime lens, so it's not really a direct competitor, but it shows what you can get in terms of bokeh and low-light performance if you're willing to give up zoom flexibility entirely. The Sigma's real niche is being the lightest full-frame zoom with a genuinely fast wide end, and nothing else in this group matches that specific combination.

Pricing on this lens is a bit of a moving target. The only listing we're seeing right now is $823 USD, which feels steep for a lens this old and this basic in terms of features. For that money, you're in the neighborhood of some much more modern options, including lenses with stabilization and weather sealing. But the f/2.8 aperture at the wide end is the wildcard here. Most compact zooms in this price range start at f/3.5 or f/4, so you're paying a premium for that extra stop of light.

If you can find this lens used or on sale, the value proposition improves dramatically. At $400 to $500, it becomes a much more interesting option for Canon EF shooters who want a lightweight walkaround zoom with real low-light chops at the wide end. At full retail, though, you're paying a lot for a lens that lacks modern conveniences and has a lukewarm track record with actual buyers.

The Sigma 28-70mm f/2.8-4 DG Aspherical is one of those lenses that makes you do a double take when you read the spec sheet. A full-frame zoom that starts at f/2.8 on the wide end, weighs just 244g, and covers the classic 28-70mm walkaround range. On paper, that's a compelling little package for Canon EF shooters who want something light enough to carry all day without giving up the ability to blur a background when the light gets interesting.

Who's this for? Honestly, it feels aimed at the photographer who's tired of lugging around a 24-70mm f/2.8 that weighs as much as a small brick. You give up a bit of aperture at the long end, sure, but you get a lens that disappears into your bag. Street shooters, travel photographers, and anyone who shoots portraits casually will find a lot to like here. The 28mm wide end is wide enough for environmental shots, and 70mm at f/4 is perfectly serviceable for flattering headshots.

The catch? This is an older design. No stabilization, no weather sealing, and autofocus performance that our database ranks as dead average. The customer rating of 3.1 out of 5 from 28 reviews also suggests real-world experiences have been mixed. But the aperture and bokeh rankings are genuinely strong, sitting in the top 15% of lenses we track. So there's real optical character here, even if the overall package feels a bit dated.

If you shoot a lot of video, skip this lens. The lack of stabilization combined with the variable aperture means your footage will be shaky and your exposure will shift as you zoom. Modern stabilized lenses from Tamron or Canon will serve you much better. Similarly, if you shoot in harsh conditions, the lack of weather sealing is a real liability. Dust, moisture, and temperature swings can all cause problems over time.

If you mostly shoot at the long end of the zoom range, this lens also falls short. By 70mm you're at f/4 with no stabilization, which is a frustrating combination for portraits or events in anything less than bright light. A used Canon 24-70mm f/2.8 or a stabilized 24-105mm f/4 would be a better fit for that kind of work. And if you're on a tight budget, the $823 USD asking price is hard to justify when there are modern APS-C options with more features for less money.

If you're a Canon EF shooter who values portability above all else and you do a lot of shooting at the wide end, this Sigma is worth a look. The f/2.8 aperture at 28mm is a real asset, and the bokeh quality is better than you'd expect from a lens this small. Street photographers and travel shooters will appreciate the 244g weight and the compact 62.5mm length. You can carry this thing all day and barely notice it.

But if you shoot a lot at 70mm, need stabilization for handheld video or low-light stills, or you're planning to use this in challenging weather, look elsewhere. The variable aperture means you're at f/4 by the long end, and the lack of stabilization makes those slower apertures even more painful in dim conditions. The mediocre autofocus and the concerning customer rating also give us pause. This is a lens with a specific sweet spot, and outside that sweet spot, it shows its age.