In summary
Mid-range zoom lenses are standard acquisitions for photographers and videographers at all levels because they cover some of the most frequently used focal lengths.
The new FE 28-70mm f/2 GM is targeted at users who really need lens speed, as well as those who would like to replace a set of prime lenses with a single zoom lens without sacrificing lens speed or image quality.
Full review
Announced on 19 November 2024, this lens is Sony’s first GM zoom lens with a constant f/2 maximum aperture, which is a stop brighter than the FE 24-70mm f/2.8 GM II lens (which is less than half its price and dates back to April 2022 and which we haven’t yet reviewed). The new 28-70mm f/2 lens isn’t quite as wide in coverage and is 16 mm longer and 191 grams heavier but it has a faster and more up-to-date AF system and more complex optical design. It also boasts a de-clickable aperture ring, making it better suited to hybrid stills and movie shooters and videographers. We reviewed this lens on the new Sony Alpha 1 Mark II camera, which is reviewed separately.
Angled view of the Sony FE 28-70mm f/2 GM, shown without the bundled lens hood. (Source: Sony.)
The optical design for the FE 28-70mm f/2 lens contains 20 elements in 14 groups and includes three XA (extreme aspherical) elements manufactured using new techniques that ensure high corner-to-corner resolution at f/2 throughout the zoom range. In addition, one ED (extra-low dispersion) element and three Super ED elements minimise axial chromatic aberration as well as lateral chromatic aberration.
This diagram shows the positions of the exotic glass elements in the optical design of the Sony FE 28-70mm f/2 GM lens. (Source: Sony.)
Nano AR Coating II is used to suppress flare, while a fluorine coating on the exposed lens elements repels moisture and dust and makes the lens easy to keep clean. Autofocusing is driven by four XD (extreme dynamic) linear motors, which are responsive enough to keep pace with the camera’s 120 fps continuous shooting speeds or high-speed video recording at up to 240 fps. A floating focus design maintains high image quality throughout the focusing range.
The minimum focus is 38 cm throughout the zoom range, with a maximum magnification of close to one quarter life size at 70mm. An 11-bladed iris diaphragm creates circular apertures for smooth rendering of out-of-focus areas.
Focus breathing has been greatly reduced optically and the lens supports the Breathing Compensation function in select Sony cameras to effectively eliminate angle of view shifts while changing the zoom position.
The short-throw zoom design means the lens only extends less than 1.8 cm when changing from the 28mm to the 70mm positions. Despite not being a true internal zoom, this means users won’t need to re-adjust gimbal settings when changing the zoom position.
The lens is supplied with the usual front and end caps plus a cylindrical lens hood, which features a locking button and a filter window. The hood can be reversed over the lens for transport and storage. Also supplied is a smart, semi-rigid carrying pouch with a shoulder strap and zip closures.
Who’s it For?
Mid-range zoom lenses are standard acquisitions for photographers and videographers at all levels because they cover some of the most frequently used focal lengths. Whether this lens is right for you will depend upon your budget, the kinds of shots you take and the conditions in which you normally shoot.
The new FE 28-70mm f/2 GM is targeted at users who really need lens speed, as well as those who would like to replace a set of prime lenses with a single zoom lens without sacrificing lens speed or image quality. You pay a price for this convenience – in both size and weight and expenditure – and it’s not insubstantial.
Sony already lists another 28-70mm lens on its website, the FE 28-70mm f/3.5-5.6 OSS, which was launched in October 2013 and initially only offered in the α7 kit. That lens is a completely different product but it’s still available and selling for about AU$300 if you’re happy to do some comparison shopping. It could be a handy option for cash-strapped photographers looking to cover the 28-70mm zoom range and, although it’s made mostly from industrial plastic, we rated it as an average-to-good performer.
A comparison table showing the similarities and differences between the three lenses is shown below.
| FE 28-70mm f/2 GM | FE 28-70mm f/3.5-5.6 OSS | FE 24-70mm f/2.8 GM | |
| Picture angle | 75-34 degrees | 84 to 34 degrees | |
| Minimum aperture | f/22 | f/22-f/36 | f/22 |
| Lens construction | 20 elements in 14 groups | 9 elements in 8 groups | 18 elements in 13 groups |
| Exotic elements | 3 XA, one ED and 3 Super ED elements | 3 aspherical and one ED glass element | one XA, one ED and one Super ED glass element |
| Diaphragm Blades | 11 (circular aperture) | 7 (circular aperture | 9 (circular aperture) |
| Weather resistance | Dust- and moisture-resistant | ||
| Focus drive | Four XD (extreme dynamic) linear motors | Linear motor | Direct drive Super Sonic Wave Motor (DDSSM) |
| Stabilisation | No (Sony Alpha cameras include sensor-shift stabilisation) | Optical SteadyShot | No (Sony Alpha cameras include sensor-shift stabilisation) |
| Minimum focus | 38 cm | 30-45 cm | 38 cm |
| Maximum magnification | 0.23x | 0.19x | 0.24x |
| Filter size | 86 mm | 55 mm | 82 mm |
| Dimensions (Diameter x L) | 92.9 x 139.8 mm | 72.5 x 83 mm | 87.6 x 136 mm |
| Weight | 918 grams | 295 grams | 886 grams |
| Standard Accessories | Front and rear caps, ALC-SH182 lens hood, soft case | Front and rear caps, ALC-SH132 lens hood | Front and rear caps, ALC-SH141 lens hood |
| RRP at launch | AU$5,299 | AU$399 | AU$3499 |
Build and Ergonomics
As expected for a GM-class lens, the FE 28-70mm f/2 GM is solidly constructed with a smooth matte black cladding on what feels like a mostly metal base. With an overall length of almost 140mm and a weight of 918 grams, this lens appears substantial, even when mounted on Sony’s Alpha 1 II camera body.
The front element is approximately 65 mm in diameter and surrounded by a stepped plastic border that is partially ribbed and carries the minimum focus of the lens (0.38 m/1.25 ft) and the filter thread diameter (86 mm). The lens surface is fluorine coated to repel moisture and dust particles. A bayonet mounting for the petal-shaped lens hood surrounds its outer edge.
The focusing ring is located roughly 14 mm behind the front rim of the lens. It’s 21 mm wide and covered in ribbed, rubber-like cladding. This ring turns through a full circle when the camera’s power is off but operates smoothly in manual focus mode.
Immediately behind the focusing ring is a fixed, 17 mm wide section of the outer barrel that carries a red ‘G’ label plus the two focus hold buttons and the AF/MF switch.
Behind it is the 38 mm wide zoom ring, which has ribbed, rubber-like cladding covering a 34 mm wide band around its leading edge. The trailing edge of the ring is stamped with settings for the 70mm, 50mm, 35mm and 28mm focal lengths, which are aligned with the white marker on the 3 mm wide section of the barrel behind the ring.
Zooming from 28mm to 70mm extends the length of the lens barrel by 10 mm. Fortunately, focusing is internal and the zoom extension doesn’t change the lens balance, enabling this lens to be used with a gimbal. The inner barrel doesn’t rotate, either, so there’s no angular change when you’re using angle-critical attachments.
The aperture ring is located directly behind the zoom ring. It’s 13 mm wide and carries markings in full f-stop increments between f/2 and f/22, with an ‘A’ position at the f/22 end for setting auto aperture selection. Intermediate marks between the f-stops denote 1/3 EV increments.
The Click On/Off and iris lock switches are located on the 20 mm wide sloping section of the outer barrel aft of the aperture ring, which leads on to a straight 11 mm wide section of the barrel that ends in the chromed metal lens mount. The lens name is embossed in silver on this band, along with details of the mount and other information.
Inside the mount are ten gold-plated contacts for passing signals between the lens and the camera body. The petal-shaped lens hood supplied with the lens has a locking button to prevent it from being accidentally dislodged and a sliding hatch that lets you rotate filters easily. It can be reversed on the barrel for transport or storage.
Performance
The review lens came close to meeting expectations for the test camera’s 50-megapixel resolution with JPEG files in our Imatest tests. Results were constantly high for aperture settings between f/2 and f/11 around the centre of the frame.
However, resolution declined sharply close to the edges of the frame, especially at wider apertures. Diffraction caused a sudden plunge in resolution at f/16, as shown in the graph of our test results from our JPEG tests below.
Not unexpectedly, ARW.RAW files, which we converted into 16-bit TIFF format with Adobe Camera Raw, were higher than those for JPEGs. The best results were obtained at f/4.5 with the 70mm focal length, where the resolution figure just exceeded expectations for the camera’s sensor in the centre of the frame.
Because Sony cameras apply corrections for the main aberrations, chromatic aberration, vignetting and distortion by default, we switched them off in the camera and tried to base our test results on converted ARW.RAW files.
Unfortunately, the raw files from the α1 II contained ‘baked-in’ profiles for chromatic aberration that we were unable to disable. Consequently, our Imatest software showed both JPEGs and the TIFFs we obtained from the camera’s raw files to be relatively free of this aberration. We also found no signs of coloured fringing in test shots.
Because Sony cameras apply corrections for vignetting and distortion by default we switched them off in the camera and based our test results on converted ARW.RAW files. Even then we had to disable the automatic profile corrections applied by Adobe Camera Raw before the files could be evaluated.
We observed some vignetting at f/2, for the four focal lengths we investigated: 28mm, 35mm, 50mm and 70mm. Corner darkening was greatest at 28mm and least at 70mm, which is to be expected. Also expected was the reduction in darkening as the lens aperture was stopped down with most visible vignetting disappearing by f/3.2 with the 28mm focal length and f/2.8 at 70mm.
Rectilinear distortion ranged from barely visible barrel distortion at 28mm and 35mm to very slight pincushion distortion at 70mm. Switching on the in-camera corrections effectively eliminated both vignetting and distortions and most raw file converters will also correct them both by default, so neither is a serious issue.
The review lens handled backlit subjects quite well and resisted flaring under most conditions. Sharp 22-pointed sunstars were possible at f/22 with all focal length settings. Most were associated with one or two just noticeable flare artefacts.
The minimum focus distance of 38 cm is only suitable for close-ups of larger flora and fauna. As usual, bokeh in wide-aperture shots is influenced by the selected lens aperture as well as the background lighting.
With evenly-lit backgrounds, the f/2 maximum aperture produced some nice, softly-blurred backgrounds, although stopping down to f/3.2 caused brighter highlights to show discernible edges, as shown in the Samples section of this review.
Autofocusing performance with the α1 II camera was generally very good, thanks largely to the fast linear autofocus motors. We also found the lens had no issues focusing in very low light levels.
Although the review lens showed some minor focus breathing issues, on the whole we found it to be well controlled, aided by Sony’s Breathing Compensation automatic in-camera corrections. Focus pulls were also smooth and well damped and both focus and exposure transitions between one subject and another were equally smooth. Subject tracking was as fast and accurate as we’ve seen from any lens we’ve tested, in part due to the improved subject detection capabilities in the camera used for our tests.
Conclusion
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SPECS
Picture angle: 75-34 degrees diagonal (54-23 degrees with APS-C crop)
Minimum aperture: f/22
Lens construction: (including 3 XA, one ED and 3 Super ED elements) Nano AR Coating II coatings
Lens mounts: Sony E-mount
Diaphragm Blades: 11 (circular aperture)
Weather resistance: Yes; rubber ring around mount plus silicone gaskets at movable joints along lens barrel
Focus drive: Four XD (extreme dynamic) linear motors, internal focusing design
Stabilisation: No (Sony Alpha cameras include sensor-shift stabilisation)
Minimum focus: 38 cm
Maximum magnification: 0.23x
Filter size: 86 mm
Dimensions (Diameter x L): 92.9 x 139.8 mm
Weight: 918 grams
Standard Accessories: Front and rear caps, ALC-SH182 lens hood, soft case
Distributor: Sony Australia
TESTS
Based on JPEG files taken with the Sony α1 II camera.
Based on ARW.RAW recorded simultaneously and converted into 16-bit format with Adobe Camera Raw.
SAMPLES
Vignetting at 28mm.
Vignetting at 35mm.
Vignetting at 50mm.
Vignetting at 70mm.
Rectilinear distortion at 28mm.
Rectilinear distortion at 35mm.
Rectilinear distortion at 50mm.
Rectilinear distortion at 70mm.
31mm focal length, ISO 250, 1/40 second at f/9.
56mm focal length, ISO 100, 1/80 second at f/5.6.
Close-up at 70mm focal length, ISO 100, 1/50 second at f/2.8.
Bokeh in close-up at 70mm focal length, ISO 100, 1/200 second at f/3.2.
Sunstars at 28mm focal length, ISO 100, 1/50 second at f/22.
Sunstar at 35mm focal length, ISO 100, 1/50 second at f/22.
Sunstars at 50mm focal length, ISO 100, 1/50 second at f/22.
Sunstar at 70mm focal length, ISO 100, 1/40 second at f/22.
70mm focal length, ISO 100, 1/250 second at f/3.5.
45mm focal length, ISO 100, 1/500 second at f/7.1.
50mm focal length, ISO 200, 1/125 second at f/3.2.
46mm focal length; ISO 100, 1/100 second at f/3.5.
70mm focal length, ISO 400, 1/200 second at f/2.8.
56mm focal length; ISO 200, 1/60 second at f/5.6.
50mm focal length, ISO 160, 1/50 second at f/8.
70mm focal length, ISO 100, 1/125 second at f/8.
70mm focal length, ISO 100, 1/1600 second at f/2.
Additional image samples can be found with our review of the Sony α1 II camera.
Rating
RRP: AU$5,299
- Build: 9.1
- Handling: 8.9
- Image quality: 9.0
- Autofocusing: 9.0
- Versatility: 8.9
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