Sigma 120-300mm f/2.8 DG OS HSM Sports

SLRgear Review
July 24, 2013
by William Brawley

The Sigma 120-300mm ƒ/2.8 DG OS HSM Sports lens is the first telephoto lens produced by Sigma as part of their Sports ("S") series lenses under their new Global Vision strategy. Serving as a replacement for the previous model, the Sigma 120-300mm ƒ/2.8 EX DG OS HSM APO, the new lens features redesigned mechanics and exterior construction. It's also heavier than the previous model, weighing in at around 8 lbs. with the hood and tripod foot attached, compared to the 6.5 lbs. of the old version. It's also slightly larger in length and width.

The new Sigma 120-300mm lens is heavy set of glass that is thankfully bundled with a large, solid tripod ring attachment and optical stabilization technology that Sigma says provides up to 4 stops of stabilization. In terms of glass construction, the new 120-300mm lens is similar to the old model with 23 elements in 18 groups with a large front element needing a 105mm filter. Two elements within the lens are made of "FLD" glass, which Sigma describes as similar to fluorite crystal as well as a single "SLD" glass element all working to help reduce chromatic aberration.

The lens is designed for full-frame cameras, but works just as well on sub-frame cameras. The constant ƒ/2.8 aperture is ideal for sports and action photographers who need the most light possible in all kinds of conditions, to ensure a fast shutter speed, not to mention great subject/background separation. Like most telephoto lenses, it's also designed to accept teleconverters for even greater focal length coverage. The Sigma 120-300mm ƒ/2.8 Sports lens is a professional-grade lens with a solid build and dust- and splash-proof weather sealing.

Like Sigma's other Global Vision lenses, the Sigma 120-300mm ƒ/2.8 DG OS HSM Sports lens is compatible with Sigma's new USB Dock, which allows users to customize any front or back focusing they might experience, as well as update the lens' firmware, or modify the Optical Stabilization presets.

The Sigma 120-300mm ƒ/2.8 DG OS HSM Sports is currently available for Canon, Nikon and Sigma mounts for $3,599 and ships with a large lens hood, removable tripod ring, soft case, neck strap plus front and rear caps.

Sharpness
The Sigma 120-300mm ƒ/2.8 Sports lens is very good optically, producing very sharp images on both full-frame and sub-frame cameras. The graphs at right show very slightly sharper results on the sub-frame body than the full-frame one, but the amount of difference is less than or equal to 0.2 of our arbitrary blur units, an amount that's well within the error margin of our tests, and a level that's completely indiscernible.

We tested the lens at three different focal lengths, 120mm, 193mm and 300mm. At 120mm and ƒ/2.8, both full- and sub-frame cameras show excellent results, particularly in the center. On the full-frame camera, there is a slight decrease in sharpness toward the edges, but it's so minor that it might not be noticeable in real-world shooting. As expected, sharpness increases significantly as you stop down, with ƒ/5.6 being the sweet spot for 120mm. As you stop down further to smaller apertures like ƒ/11-ƒ/22, you start to see some softness from diffraction limiting occurring, but it's surprisingly minor.

Zooming to 193mm, we see a little more edge/corner softness at ƒ/2.8 than we did at 120mm, particularly on the full-frame camera. Again, stopping down to ƒ/5.6 provides spectacularly sharp results on both cameras, and like we saw at 120mm, diffraction limiting at extremely small apertures is not severe.

Finally, at 300mm, we don't see as sharp an image as we saw at the other focal lengths when shooting wide open. However, if we stop down to ƒ/4, we begin to see familiar sharpness values as before. At 300mm and ƒ/5.6 on a full-frame camera, we saw the best sharpness of that focal length, while ƒ/4 and ƒ/5.6 on the sub-frame camera were pretty much tied for sharpness. And just as before, stopping down the extreme apertures of ƒ/16-ƒ/22 only showed minor softening from diffraction limiting.

Chromatic Aberration
Chromatic aberration was very well controlled on this new Sigma 120-300mm lens, thanks to the two FLD elements and single special low dispersion (SLD) glass element. At 120mm, we see a bit more "maximum" aberration values on the sub-frame images compared to the full-frame, however the average values are very similar between both cameras, and overall quite low. (Note that aberration here is reported as a percentage of the frame height, so the same physical amount of CA will measure higher on a sub-frame camera than a full-frame one.) On both cameras, the CA is reduced when stopping down, leveling off between ƒ/5.6 and ƒ/8. Both cameras show very similar CA values for 193mm, which are much lower than at 120mm, and the maximum vs. the average values are closer together. As before, there's a gradual decrease in CA as you stop down.

At 300mm, however, there's a slightly different trend – chromatic aberration increases as you stop down, albeit very slightly. It's again slightly more noticeable on the sub-frame camera. On a full-frame camera, the values for maximum and average are both very low, while we see a bit more difference in average vs. maximum values from the sub-frame camera.

Shading (''Vignetting'')
Like CA, vignetting is very well controlled on the Sigma 120-300mm, and strikingly so on the sub-frame body, which is to be expected with a full-frame lens on a smaller sensor. On the full-frame camera, the Sigma lens shows nearly identical values for 120mm and 193mm at about 0.5 stops of light loss in the corners at ƒ/2.8. The vignetting sharply decreases as you stop down, and at ƒ/8 the light loss is less than 0.125 of a stop. For 300mm, vignetting is a little stronger on a full-frame camera, at about 0.75-stops of light loss in the corners at ƒ/2.8. The vignetting quickly decreases as you stop down, reaching the less than 0.125 of a stop like the other focal lengths once you get to ƒ/16 and beyond.

On the sub-frame body, vignetting is practically non-existent past ƒ/4 for all three focal lengths we tested. At ƒ/2.8, we see under 0.25 EV of light loss for all three focal lengths. Between ƒ/5.6 and ƒ/16, vignetting is close to zero EV light loss.

Distortion
The average distortion for the Sigma 120-300mm ƒ/2.8 Sports lens is very low on both full- and sub-frame cameras. At 120mm, there's practically zero distortion when looking at the average values, and just a hint of pincushion distortion in the maximum values. Zooming out to longer focal lengths, barrel distortion increases slightly: more so on the full-frame body with less 0.25% at 300mm, while just hint (~0.125%) for the sub-frame body.

When looking at the maximum values, we see an increase in pincushion distortion as you increase in focal length, however it's still very low: less than 0.5% for full-frame and less than 0.25% for sub-frame.

Autofocus Operation
The Sigma 120-300mm lens autofocuses very quickly, taking about 1 second to rack through the full range from minimum focus distance to infinity. The autofocus on the new Sigma lens feels very fast and silent (thanks to Sigma's HSM, or Hyper Sonic Motor focusing system), and locks on to subjects easily with no hunting. Manual focusing is also available, both while AF is engaged (thanks to the ring-type HSM motor), as well as a full manual focusing option. During focusing, the front element of the lens does not rotate or extend (it focuses internally). The minimum focusing distance is 59.1 to 98.4 inches, increasing as you zoom from shorter to longer focal lengths.

Macro
This lens has a minimum focusing distance of 4.9 feet (1.5 meters) and is not designed for macro shooting.

Build Quality and Handling
The first thing you notice about this lens is its sheer size. This is not a small optic, nor is it a lightweight one. With the large lens hood and hefty tripod ring attached, the whole assemblage tips the scale at just over 8 pounds! While the new Sigma 120-300mm ƒ/2.8 DG OS HSM S may feel like it's made entirely of metal, it actually incorporates Sigma's new Thermally Stable Composite (TSC) material, just like Sigma's other new Global Vision lenses. The new TSC is similar in texture and strength to metal, but is more suited for tough weather conditions and temperature changes than polycarbonate plastics (it features similar thermal characteristics to aluminum). Sigma says it's designed to allow for high-precision construction and combines well with other metal components. We're not sure if the entire barrel and hood are constructed with the new TSC material or if there is a mixture of metal and TSC components, as it all feels a lot like metal to the touch. Regardless, the lens feels extremely solid, and the build quality is excellent.

When it comes to hand holding this lens, it's definitely not your average walk-around lens! The large glass elements in the front shift the balance of toward the front, and thankfully the tripod foot includes 3 mounting holes, allowing users to properly balance the lens on a tripod or monopod depending on the size and weight of their camera body, and whether they're using any other attachments like teleconverters. While hand holding this lens is not impossible, it's large and heavy, and using a monopod (at least) is highly recommended if you plan on shooting for any length of time. You'll also find attachment points on the tripod ring itself for its own neck strap. Like most lenses that feature a tripod foot or ring, the tightening knob allows you to rotate the camera and lens into a vertical orientation quickly without having to fiddle with your tripod head, avoiding potentially unstable tripod arrangements given the lens' size and weight.

The Sigma 120-300mm lens' metal-like construction has a smooth, matte black finish. Gone are the days of Sigma's old rubberized black coating. It looks and feels great, although it's very bulky and can be a bit unwieldy if you're not used to lenses of this size. Compared to the previous version, Sigma states that this model is dust and splash-proof, but not fully waterproof – more like "weather-sealed." The lens mount does feature a rubber gasket for environmental sealing with the camera.

Inside the big black barrel sit 23 lens elements in 18 groups, two of which are FLD glass elements, which Sigma claims are optically identical to fluorite glass. There is also a single SLD (Special Low Dispersion) element. The FLD and SLD elements help reduce chromatic aberration. The lens also features a 9-bladed aperture.

The separate focusing and zooming rings are wide with large rubber ribs for an easy grip. The zoom ring is larger at about 2.25 inches and has a two-tiered raised portion for easy identification without looking. The focus ring, on the other hand, is smaller at about 1.25 inches, with slightly smaller rubberized ribs. The zoom ring is farther away and the focus ring is closer to the camera.

Both rings rotate very smoothly, although the zoom ring takes a bit of effort to turn (almost requiring your whole hand). I found the zoom ring a bit awkward to rotate if you are hand holding the lens, particularly with the tripod foot attached, as you tend to rest your hand under the tripod foot, and it takes some oomph to rotate the zoom ring. The focus ring, however, is buttery smooth and easy to turn. The focus ring will rotate all the way around the lens and has soft stops at close and infinity distances. The zoom ring turns less than 90 degrees.

As with focusing, the front element of the lens neither rotates nor extends when zooming, which allows for easy use of screw-on filters like circular polarizers (the Sigma 120-300mm takes 105mm filters; no option for a drop-in filter). Like many high-end lenses, the Sigma 120-300mm f/2.8 Sport has a constant aperture, meaning the aperture doesn't change automatically when zooming.

Other exterior features include a focusing distance window and marked focal lengths of 120mm, 150mm, 180mm, 200mm, 250mm and 300mm. There is also a small panel of switches for AF/MF toggle, focus limiting (full, 10m to infinity, and minimum to 10m), image stabilization settings (1,2 and Off) and a custom preset switch, which can be programmed via Sigma's USB Dock, giving users two sets of customized AF performance and image stabilization tweaks.

This updated model also sports a redesigned lens hood, which feels similar in construction to the barrel (either TSC or metal). The lens hood locks on to the front, bayonet style, with a locking screw and adds about 4.25 inches of length to the lens.

Alternatives
The closest, most obvious alternative to the new Sigma 120-300mm ƒ/2.8 DG OS HSM Sports lens is its predecessor, the Sigma 120-300mm ƒ/2.8 EX DG OS APO HSM, which, although listed as discontinued on Sigma's website, is still for sale at camera stores like B&H, at least as of this writing in late July, 2013. Sigma indicates that the new 120-300mm lens features new mechanics and improved performance compared to the old model, and the new version does feature cosmetic changes in the barrel construction, and adds features like weather sealing and a new AF algorithm for smoother autofocusing. Both models have a lot of similarities in lens element construction – 23 elements in 18 groups with 1 SLD element and 2 FLD Elements. They both also have 9-bladed apertures, HSM focusing and image stabilization. The big difference is price. The new model retails for $3,599, while the old one can be had for $2,499. For the weigh-conscious, the older model is also lighter at 6.5 lbs. While we haven't tested the older models, reports are saying the new version is optically superior.

There aren't really any other direct alternatives from competing manufacturers that give you the ƒ/2.8 constant aperture in a 120-300mm zoom lens. There are some alternatives that would give you similar focal lengths and/or would be used for similar purposes, but not all in one package like the Sigma.

On the Canon side of things, the closest lens would be the Canon EF 300mm ƒ/2.8 L IS II, which gives you a 300mm focal length with an ƒ/2.8 aperture and image stabilization, all with fantastic image quality. The two major downsides are a) you are limited to the single focal length and b) the price. The Canon lens is a whopping $6,799 compared to the Sigma's $3,599. Similarly, for Nikon users there's the Nikon 300mm ƒ/2.8G ED VR II AF-S lens, but again, featuring only a single focal length and a much higher price tag ($5,799).

Another option would be a 70-200mm ƒ/2.8 IS (or VR, depending on brand) plus a 1.4 teleconverter. Taking the Canon EF 70-200mm ƒ/2.8 L IS II plus the Canon 1.4X Extender EF III gives you a similar zoom range (though not exactly the same), but you lose a stop of light (now down to ƒ/4), worse image quality and slower AF speed thanks to the teleconverter. Nikon users have the Nikon 70-200mm ƒ/2.8G ED VR II AF-S and either the Nikon 1.4X AF-S TC-14E II or Nikon 1.7X AF-S TC-17E II teleconverters.

Conclusion
The Sigma 120-300mm ƒ/2.8 DG OS HSM Sports lens is a fantastic piece of glass that features professional-level image quality, build quality and features at a price point that, at least at the time of this review, are not matched by any other competing lens manufacturer.

The new Sigma 120-300mm lens is the first "Sports" model in Sigma's new Global Vision line of lenses. This long telephoto zoom combines the flexibility of a zoom with the image quality and constant ƒ/2.8 aperture normally seen on higher-priced telephoto prime lenses. The addition of image stabilization makes it a no-brainer for sports and action photographers that shoot in all sorts of environments and weather conditions. It's well-suited outdoors, for football or baseball season or indoors, courtside at a basketball game. Nature and wildlife photographers should take a look as well. The zoom really makes this a very versatile lens.

Users who are in the market for this type of lens are probably already aware of the heft and size that they demand, and the Sigma 120-300mm ƒ/2.8 DG OS HSM Sports is no exception. At around 8 pounds and over 15 inches long, this is a heavy, large piece of equipment. However, despite the weight and bulk, this Sigma tele-zoom allows you to save quite a bit of dough compared to competing models from other manufacturers, while still having excellent build quality, as well as excellent image quality.

Product Photos

Sample Photos

Click here for Real-world Gallery Images on our Flickr page!

The VFA target should give you a good idea of sharpness in the center and corners, as well as some idea of the extent of barrel or pincushion distortion and chromatic aberration, while the Still Life subject may help in judging contrast and color. We shoot both images using the default JPEG settings and manual white balance of our test bodies, so the images should be quite consistent from lens to lens.

Still Life shot

VFA target

As appropriate, we shoot these with both full-frame and sub-frame bodies, at a range of focal lengths, and at both maximum aperture and ƒ/8. For the ''VFA'' target (the viewfinder accuracy target from Imaging Resource), we also provide sample crops from the center and upper-left corner of each shot, so you can quickly get a sense of relative sharpness, without having to download and inspect the full-res images. To avoid space limitations with the layout of our review pages, indexes to the test shots launch in separate windows.