As far as lenses go, the Sigma 60-600mm F4.5-6.3 DG DN OS Sports ($1,999) is a hefty one. It's the largest, heaviest, and longest-zooming lens the company offers with a made-for-mirrorless optical formula. It's also one to consider if you're in need of a zoom that can swing from standard to extreme telephoto, especially if you're looking for a zoom that can keep up with high-pixel sensors. We don't see it as quite the crowd-pleaser as another Sigma, though, the 150-600mm F5-6.3 DG DN OS Sports, our Editors' Choice telezoom, but creators who need wider coverage will still enjoy great performance if they get the 60-600mm instead.

Not Quite Carry-Friendly

Let's face it, lenses that go to telephoto extremes—and 600mm qualifies—are a size up from zooms that finish around 400mm. But photographers still use them, as the extra reach is useful for wildlife, field sports where you're positioned far away from the action, and other situations where you want to punch in for a tight view.

Even so, the 60-600mm goes slightly beyond the norm. It measures 11.0 by 4.7 inches (HD) and tips the scales at 5.5 pounds. I'm not ashamed to admit that after a couple of weeks of lugging it around on my morning walk, the arthritis in my strap shoulder was screaming at me to pick up a more sensible lens.

And there are more carry-friendly options to consider—the Tamron 50-400mm F4.5-6.3 is a similarly minded lens that comes in at 2.5 pounds. If you're after 600mm reach, the Sigma 150-600mm Sports is by no means light, but it's not quite as much of a strain to carry at 4.6 pounds. The Tamron 150-500mm F5-6.7 provides a comfortable middle ground at 4.1 pounds.

Tamron makes its competing zooms for Sony E-mount, while Sigma offers up both this 60-600mm and its 150-600mm for two systems: Sony and L-mount Alliance. The type of camera you own has some influence over your options, and Sony owners typically have more choices than photogs using Leica, Panasonic, or Sigma L-mount bodies.

The construction quality is as robust as you'd expect from Sigma's top class of lens. The barrel is a mix of magnesium, carbon fiber, and thermally stable composite, and is matched with a carbon fiber hood. The hood latches onto the outer barrel and tightens with a thumb screw. It's reversible for storage, and can be used along with a slip-on soft lens cap to protect the front element. Threaded filters are supported, but you'll need to save room in your budget as the 105mm size tends to be expensive.

The lens is weather sealed as well. Sigma doesn't give it an IP rating, but you can use it comfortably in rainy, snowy, or dusty conditions along with a pro camera. The front element is coated with anti-smudge fluorine, a material that repels water drops and makes it easy to wipe away stray thumbprints with just a microfiber cloth.

A rotating tripod collar with an Arca-Swiss compatible tripod foot are integral to the design; the collar supports 360-degree rotation with 90-degree click stops and is secured with a thumb screw.

Customers buying the lens in L-mount are able to match with a 1.4x or 2.0x teleconverter to extend its focal range. It's a feature missing from the Sony version of the lens—Sigma doesn't offer its teleconverters for Sony cameras, and the Sigma lens does not work with Sony's GM series teleconverters.

Handling and Controls

As you'd expect from its mass, the 60-600mm is not the easiest lens to use for handheld photography. It's a two-hander for sure; you'll use your right hand to hold the camera as normal, and your left will come in handy to cradle the zoom and take some weight off your camera. A monopod is a useful add-on if you like to be somewhat mobile with your camera, and a tripod is a good match if you prefer to set up and work from a fixed location.

The two big control rings, for zoom and manual focus, are both finished in a tough, rubberized wrap, each with raised ridges so you can enjoy a ready grip. The zoom ring requires some effort to turn—the optical block accounts for much of the weight, after all. Even so, it's not unmanageable, and push-pull action is workable too, if you prefer.

The barrel does creep outward when facing down—you cannot negotiate with gravity. An on-barrel Lock switch is included to prevent this; it keeps the lens set to its shortest 60mm position. And much like the lock on Sigma's previous 60-600mm DG HSM Sports for SLR systems (an entirely different lens), you can also lock the lens at the 80, 100, 120, 150, 200, 300, 400, or 600mm focal lengths. Locking the zoom in at longer focal lengths is an uncommon feature, but one that wildlife specialists who use a mechanical gimbal head to pan and track birds in flight may find useful.

Sigma put three function buttons on the barrel. They're positioned mid-lens, in the same section as the Lock switch, with 90 degrees of arc between them. The four buttons are all tied to the same function, typically AF-ON, and said function is configurable via the camera menu system.

A control panel houses the remainder of the on-lens toggles. It's positioned right ahead of the mount, and accessible with your left hand when you're positioned behind the lens. The control panel toggles set the focus mode and autofocus limiter, set the optical stabilization mode, and swap between custom modes. L-mount owners are able to match the lens with the Sigma USB Dock to fine-tune focus response and other aspects of performance. Creators using the Sony system will miss this feature, though, as there's no E-mount configuration dock available.

Autofocus is driven by a new type of focus motor, at least new to Sigma. The High-response Linear Actuator (HLA) focus motor drives the lens with speed and precision, without introducing too much noise to your environment or video soundtrack. I tested the zoom with the Sony a7R IV and the lens operated as quickly as you could expect from the body. The HLA motor is quick enough to drive focus from a close to a distant subject in an instant. I've not had an opportunity to try the lens with the speedy Sony a1 or the more recent a7R V, however, both of which focus faster than the a7R IV.

In practice, the 60-600mm Sports focuses in a snap with the a7R IV, and I found it to be effective when paired with the camera's Real Time Tracking focus system in the field. The pair found focus and kept up with the moving targets I was able to find in the wild, including songbirds hopping from branch to branch and a gaggle of geese flying fairly low to the ground. Even so, Sigma isn't happy with the pre-release tracking from the lens and asked us to point out that we've been working with beta firmware. The company promises to deliver updated firmware to customers when the lens hits shelves in mid-February.

One of the appeals of the 60-600mm's extended zoom range is a reduced need to swap out lenses in the field. To cement its place as an all-arounder, the 60-600mm does double duty as a capable macro lens. The lens focuses as close as 17.8 inches when zoomed out, and does its best macro work at the 200mm focal length, where it is able to capture subjects at 1:2.4 life-size magnification. Of course, the big lens isn't good for everything—you won't want to look to it for use in low light, nor does it make any sense if you care about putting together a carry-friendly kit.

Stabilization is built in and is rated for up to seven stops of compensation at 60mm and six stops at 600mm. In practice, I was able to snag 1/8-second handheld photos at 600mm with the a7R IV. As is the case with most big zooms, there are two stabilization modes available. Mode 1 is used for most situations, but you'll want to switch to Mode 2 when you're panning to follow a laterally moving subject.

Sigma 60-600mm Sports: In the Lab

I matched the 60-600mm with a 60MP camera, the Sony a7R IV, and Imatest software to check its optical performance in the lab. The pair put up excellent scores in the lab, showing better than 4,500 lines through the range. As such, we were able to test the lens with our most precise SFRplus test chart from around 60-300mm. For comparison, these scores skew a few hundred lines higher than the Sigma 150-600mm Sports for mirrorless systems.

I swapped to a smaller chart for tests at 600mm, one that's not quite as precise for measuring high-pixel cameras. Even so, the 60-600mm kept pace with results from the Sigma 150-600mm tested on the same chart. Within our scope of testing, it's clear that there's no downside from a resolution perspective between the two—if anything, the 60-600mm is a sharper lens, in spite of its wider angle of coverage. Of course, there's no question that Sigma has put more glass inside to get there. The 60-600mm's optical formula incorporates 27 elements arranged in 19 discrete groups.

That's not to say the 60-600mm is without flaws, they just aren't major ones. I spotted some lateral chromatic aberration in landscape scenes made toward the 60mm end, especially around slightly defocused tree branches. This type of false purple color isn't too tough to remove with software. I also spotted some longitudinal chromatic aberration (LoCa) in the places where I expected to see it. It shows up as false purple and green color in defocused areas of your photo. I spotted it in defocused tree branches, and also noted some orange halos when photographing into a strong backlight. All and all the aberrations aren't dealbreakers. The purple fringing (lateral) effect doesn't show up too often, and is easy to remove if you do spot it, and LoCa is a situational concern, not an all-the-time issue.

We're reviewing the lens ahead of release, so an Adobe Raw correction profile isn't yet available to compensate for distortion and vignette, but neither is a big problem. I spotted a bit of inward pincushion distortion in Raw images and dimmed edges when using the lens at maximum aperture. An embedded JPG correction profile takes care of both if you don't work with Raw files.

How Much Are You Willing to Carry?

I'll put it right out there: The Sigma 60-600mm F4.5-6.3 DG DN Sports is a pretty fantastic lens as long as you don't mind lugging it about. What kind of photo work you do, how you travel and carry your gear, and your general fitness all come into play when considering a lens like this, and are just as important to consider as optical quality and autofocus performance. We have few complaints about the latter—picture quality is great and focus is snappy. Build quality, too, is all pro, though the rugged construction contributes to what may be the breaking point for some: the weight.

At around 5.5 pounds, the 60-600mm might be too much for you to handle with comfort. I didn't use it as much as I would have thought, simply because my shoulder was telling me to take days off during my review period. Some may see it as no problem, though, or may look to the lens for sideline sports photography, where the standard to super telephoto range gives you some breathing room when framing wider shots. A monopod is helpful with this lens, too.

As for alternatives, the Sigma 150-600mm F5-6.3 DN DN Sports is our Editors' Choice telezoom and remains our top recommendation for most creators searching for an extra-long lens thanks to its more reasonable carry weight (4.6 pounds) and $1,499 price. If you want a telezoom with standard coverage, the Tamron 50-400mm ($1,299) offers much of the appeal with half the weight. It's among our favorite telezooms, and a good pick if you don't require the narrower angle a 600mm lens provides.