The Sony FE 12-24mm f2.8 G Master is an ultra-wide zoom lens with a constant f2.8 aperture, designed for Alpha full-frame mirrorless cameras. Announced in July 2020, it’s Sony’s 37th full-frame mirrorless lens and becomes the widest full-frame f2.8 zoom; it also means Sony now offers focal lengths from 12 to 200mm with a constant f2.8 aperture.
The FE 12-24mm f2.8 GM shares the same focal range as the earlier FE 12-24mm f4G, but with an aperture that’s one stop brighter. As a member of the G Master series, Sony also claims the f2.8 model delivers higher resolution and contrast especially towards the corners, reduced flare and ghosting, and remains rectilinear out to the extremes too. It’s inevitably larger and heavier as a result, measuring 98x137mm and weighing 847g versus 87x117mm and 565g for the earlier f4G model, but these sizes do include built-in petal lens hoods. The new lens is of course dust and moisture-resistant. Find out everything you need to know about the lens, including sample images and movies in my video review below, or keep scrolling for a written version!
Facts from the catalog
Let’s compare the Sony FE 12-24mm f2.8 GM (“Sony f2.8 GM” for short) to the Sigma 14-24mm f2.8 DG DN Art (“Sigma DN”) and Sony FE 12-24mm f4.0 G (“Sony f4.0 G”). As usual I’ve rated the features with a [+] (or [++]), when it’s better than average or even state of the art, a  if it’s standard or just average, and [-] if there’s a disadvantage.
Size (diameter x length): All three lenses have a built-in lens hood and don’t change their length when zooming – although the front element of the lenses moves. At 98 x 137mm (3.9 x 5.4in.) the Sony f2.8 GM is the biggest lens of the three. The Sony f4.0 G is pretty compact in comparison at 87 x 117mm, the Sigma DN somewhat in-between at 86 x 132mm. 
Weight: At 847g (19.9 oz.) the Sony f2.8 GM is heavier than the Sigma DN at 797g or the Sony f4.0 G at 563g. 
Optics: The Sony FE 12-24mm f2.8 GM has 17 elements in 14 groups including 5 special dispersion elements and 4 aspherical elements. This is similar to the other lenses in this comparison. To reduce reflections causing flare, glare and ghosting the Sony f2.8 GM employs Nano-coating. It also has fluorine-coating on the front element to repel water, dust, and dirt and make cleaning easier like the Sigma DN. [+]
Closest focus distance is 0.27m (0.9ft.) at 24mm focal length with a magnification of 1:6.7 which is similar to the Sony f4.0 G. This results in a working distance of only 12cm (4.7in.). The Sigma DN achieve 1:5.1 at 23cm focus distance. A magnification of 1:10 is achieved at around 0.35m focus distance with all three lenses. 
Filter-thread: None of the lenses in this comparison offer a filter-thread – their bulbous front elements prevent that. So you need to get some non-standard mounting system and a new set of filters – or use gel filters in the rear filter holder of the Sony f2.8 GM and Sigma DN. Keep in mind though that gels cannot be rotated which precludes the use of polarizers. Sony and Sigma supply a template with their lens to cut out the gels. 
Image stabilization: All three lenses in this comparison have no optical image stabilization. But the Sony A7 camera bodies provide built-in sensor-shift stabilization. 
Auto focus: Yes with built-in AF drive. Manual-focus override is by simply turning the dedicated focus ring at the front of the lens. It has a linear gearing covering the focus range in about 120 degrees. This is ideal for smooth focus pulling in videos and still precise enough for manually focusing. The Sony f4.0 G has a somewhat restricted variable gearing between 90 and 200 degrees for the full focus range and the Sigma DN offers the usual fully variable gearing. All three lenses also have an extra button which can be assigned many different functions e.g. AF-lock. [+]
Lens profile: All tree lens come with a lens profile for vignette-, CA- and distortion-compensation which can be controlled from the camera. [+]
Covers full frame/FF or smaller. Same with the other lenses. [+]
Price: The Sony f2.8 GM is 3300 EUR (incl. 19% VAT) / 3000 USD / 2900 GBP, the Sigma DN is 1450 EUR / 1399 USD / 1299 GBP, the Sony f4.0 G currently goes for 1550 EUR / 1670 USD / 1400 GBP. [-]
Aperture ring: None of the lenses in this comparison has an aperture ring. 
The lens comes with a padded pouch but no straps. [+]
Sealing: yes, a rubber grommet at the lens-mount plus further special weather-sealing throughout the construction, just like the other two lenses. [+]
The score in the “features-department” is 1[-]/6/6[+]. The Sony FE 12-24mm f2.8 GM offers a good feature set: It has a constant bright f2.8 focal ratio, a professional build including thorough weather sealing, provides for the use of rear gel filters, and starts at 12mm focal length giving a visibly wider field-of-view than other lenses starting at 14mm. But it is the largest, heaviest, and by far most expensive of the three lenses in this comparison.
If you want to cover the range of focal lengths from 14mm to 24mm there are really only two alternatives to the Sony FE 12-24mm f2.8 GM available in the native E-mount:
- Sony introduced the FE 12-24mm f4.0 G in 2017. It has a one stop slower focal ratio but this makes the lens a smaller and 30% lighter alternative to the Sony f2.8 G. And at half the price it is much more affordable although still not exactly cheap. See my Sony FE 12-24mm f4.0 G review.
- The Sigma 14-24mm f2.8 DG DN Art from 2020 might ‘only’ start at 14mm focal length giving an 8 degree narrower view on the short end than the Sonys but it still delivers enormous coverage. And although it has the same bright focal ration as the Sony f2.8 GM, Sigma managed to make the lens a bit smaller and lighter. And most importantly it is less than half the price of the Sony f2.8 GM although it has the same feature set, albeit again without that extra 2mm at the short-end. See my Sigma 14-24mm f2.8 DG DN Art review.
Other alternatives cover different focal lengths like the manual focus Laowa 10-18mm f4.5-5.6 which is currently the only full frame zoom lens starting at 10mm focal length with a recti-linear projection. Or you use older DLSR designs via mount adapter.
Here is the angle of view that the Sony FE 12-24mm f2.8 GM covers with its 2x zoom compared to the 1.7x coverage of the Sigma 14-24mm f2.8 DG DN Art:
Focus and zoom
Focus accuracy and repeatability is critical to consistently produce sharp shots. Repeatability (the accuracy of focus on the same subject after repeated focus-acquisition) of the Sony FE 12-24mm f2.8 GM at 24mm focal length is very good (measured 99.0% in Reikan FoCal) with no outliers over a series of 40 shots. There is also no focus variation whether the lens focuses from a closer distance or from infinity. At 24mm focal length the lens focuses in around 0.6 sec from infinity to 0.35m (1:10 magnification), which is faster than the Sigma 14-24mm f2.8 DG DN Art which took 0.7 sec but a bit slower than the Sony f4.0 G at 0.5 sec.
The zoom ring turns through 60 degrees and has a 17mm wide rubber surface with a good grip. It needs less force than the Sigma. The focus ring at the front is 12mm wide and moves smoothly.
AF-operation of the Sony f2.8 GM is inaudible from the outside or if you record video with the built-in microphone. Same with the Sony f4.0 G and Sigma DN.
As you pull focus, you’ll notice some focus breathing: When I adjusted the focus from infinity to 0.35m on the Sony f2.8 GM I measured a 4% decrease in magnification at 24mm focal length and at 12mm. The Sigma DN is breathing -1%, the Sony f4.0 G 1-2%.
The Sony FE 12-24mm f2.8 GM zoom lens is parfocal: When I focused the lens at 24mm and zoomed back to 12mm focus stays on the same spot. Same with the Sony f4.0 G and Sigma DN.
Next check out my quality results!