Sony 50mm f/1.2 GM (SEL50F12GM) lens
One of five Sony-branded 50mm lenses currently available for the company’s full frame α7 and α9 mirrorless cameras, the FE f/1.2 GM lens is the fastest, largest, heaviest and most expensive in the collection.
If lens speed and shallow depth of field are high on your list of priorities, this lens is definitely worth a look.
Announced in March 2021 as Sony 60th E-Mount lens, the FE 50mm f/1.2 GM (G Master) lens is one of five Sony-branded 50mm lenses currently available for the company’s full frame α7 and α9 mirrorless cameras. It’s half a stop faster than the Zeiss 50mm f/1.4 Planar T* lens, which was introduced in 2016 and the highest-priced 50mm FE mount lens to date. Featuring a sophisticated autofocusing system that can focus to within 40 cm of subjects and de-clickable aperture ring, it can be used for both stills and video work.
Angled view of the new FE 50mm f/1.2 GM (SEL50F12GM) lens, shown without the supplied cylindrical lens hood. (Source: Sony.)
The optical design of 14 elements in 10 groups (shown below) includes three XA (extreme aspherical) lens elements that help to keep resolution high across the entire image frame, including at the widest aperture. Sony’s Nano AR Coating II has been applied to control internal reflections and suppress ghosting and flare and the front element is fluorine coated to resist dust, water, oil. fingerprints and other contaminants.
This diagram shows the arrangement of lens elements in the FE 50mm f/1.2 GM lens, with the three XA elements highlighted. (Source: Sony.)
Autofocusing is driven by four XD (extreme dynamic) linear motors, arranged as shown in the diagram below. The floating focus mechanism is controlled by a dedicated lens drive algorithm. Together they provide the thrust efficiency needed for fast and accurate focusing and high tracking precision when shooting 4K video.
The four linear motors used in the focusing system of the FE 50mm f/1.2 GM lens. (Source: Sony.)
This lens is supplied with front and end caps, the ALC-SH16 cylindrical lens hood and a soft case and strap. We reviewed it on a Sony α7 Mark II camera body.
Who’s it For?
Although 50mm prime lenses are both popular and generally seen as versatile, the SEL50F12GM is somewhat different from the other Sony-branded 50mm lenses. Not only is it the fastest in the collection; it’s also the largest, heaviest and most expensive in Sony’s range. The table below provides a basic comparison of 50mm lenses currently available for Sony’s α7 and α9 full frame cameras.
|Brand||Max. aperture||Weight||Special designation||RRP (9AU$)||Focus|
|Zeiss||f/1.4||518 grams||Planar T*||$2199|
|f/2||320 grams||Loxia Planar T*||$1299|
|Sigma||f/1.4||910 grams||DG HSM Art||$1329|
|Samyang||f/1.4||585 grams||UMC II||$929|
|f/1.4||420 grams||EF II||$999|
Because of its size and price, the SEL50F12GM will probably only be sought out by photographers who need high lens speed and/or a paper-thin plane of focus for seriously defocused backgrounds. The lack of stabilisation won’t matter as most potential users will want this lens for a camera with SteadyShot IS built-in.
If you don’t need either, one of the other Sony lenses would be smaller, lighter and cheaper and still allow you to take good photos. It’s also a better choice for smaller, lighter cameras, such as Sony’s α6*** range.
Potential purchasers of the SEL50F12GM lens should note that this lens shouldn’t be used with a camera’s built-in flash, which will make it unsuitable for entry-level models. External flashguns can be used but care is required to ensure the lens doesn’t block off light and cast a shadow at the bottom of the picture.
Build and Ergonomics
As noted, this is a large and heavy lens for a 50mm prime. Weighing 778 grams without the hood, it is roughly four and a half times the weight of the 174 gram FE 50mm f/2.5 G (SEL50F25G) lens and almost three times its price.
The supplied lens hood is made from solid black plastic. It’s 47 mm deep, with 10 mm around the front edge covered in rubber to absorb impact shocks. The inner surface is flocked to suppress reflections and there’s a locking button to keep it in place, including when it’s reversed over the lens barrel.
The weather-resistant sealing in the SEL50F12GM lens. (Source: Sony.)
Like other lenses in the G Master series, this lens boasts extensive weather-resistant sealing – including aroudn the focus buttons – to prevent ingress of moisture and dust and allow the lens to be used in challenging conditions. The positions of these seals are shown in the illusration above.
The front element of the lens is roughly 45 mm in diameter and surrounded by a 10 mm wide, slightly recessed ring that carries the name of the lens, its minimum focus and filter diameter. The raised filter thread surrounds this rind, with the bayonet fitting for the lens hood on its outer edge.
The leading edge of the focusing ring begins roughly 5 mm behind the front of the lens barrel. The ring is 22 mm wide and almost totally covered in rubber ribbing. Because focusing is driven from the camera it turns though 360 degrees when power is off.
Behind the focusing ring is an 18 mm wide section of the lens barrel that carries the two focus hold buttons, which are positioned to make them easily accessible whether the camera is used in vertical or horizontal orientation. This section of the barrel also contains the AF/MF and Click ON/OFF sliders and the ‘G’ logo that denotes a G-Master lens.
The aperture ring sits behind this section. It’s approximately 15 mm wide, with ribbing around the front half to provide a secure grip and f-numbers in one-stop increments around the trailing half. A red ‘A’ beyond the f/16 mark denotes the Auto aperture setting.
The lens barrel continues for a further 13 mm; this section carrying the name of the lens in silver. It then slopes inwards for a further 18 mm before ending up after 11 mm at the edge of the lens mount.
A rubber flange surround the intersection between the black plastic of the barrel and the very solid, chromed mounting plate, which ends in a 45 mm diameter raised ring that carries the ten, gold-plated contacts for passing electronic signals between the lens and the camera.
The overall performance of this lens was very good, especially since our test shots were taken with all in-camera corrections disabled. Our Imatest tests showed it comfortably exceeded expectations for the testing camera’s 24-megapixel sensor from the centre of the frame to half-way out to the periphery. Edge resolution fell a little short, including with raw files, where resolution is generally higher.
One noteworthy aspect of our test results is the consistency of the resolution values recorded across the aperture range – even as far as f/8, where diffraction began to take effect. The graph below shows the results of our tests.
Lateral chromatic aberration remained within the ‘negligible’ band at all aperture settings and we found no evidence of coloured fringing in test shots. In the graph of our test results below, the red line marks the boundary between ‘ negligible’ and ‘low’ CA.
Autofocusing was generally accurate but only moderately fast, particularly in challenging conditions like low contrast and with dimly-lit subjects. Manual focusing is electronically controlled without a lot of tactile feedback but easy enough to use, thanks to the AF/MF switch on the lens. Focus breathing was seen as a slight increase in magnification as the lens was focused in on close subjects.
Without in-camera corrections, vignetting was obvious at the widest aperture settings but barely visible when the lens was stopped down beyond f/2.8. Slight pincushion distortion could be seen in uncorrected images but effectively addressed by in-camera corrections. Neither aberration should be problematic if the camera’s corrections are implemented, which usually occurs by default.
The minimum focus is just adequate for photographing larger flowers and similar subjects and the speed of this lens is enough to produce a very shallow depth of focus. Bokeh at wide aperture setting was quite attractive as long as background lighting was relatively even. However, we found some obvious outlining around brighter highlights, especially with backlit shots. Fortunately, highlights remained circular near the periphery of the frame.
The 11-bladed iris diaphragm can create attractive 22-pointed sunstars when the lens is stopped down and pointed at a bright light source. However, care is required in these shooting conditions as the concentrated light from the sun can damage pixels on the image sensor during exposures longer than about a quarter of a second if the camera is pointed directly at the full sun.
Please Login or Register to access the Conclusion.
Picture angle: 47 degrees
Minimum aperture: f/16
Lens construction: 14 elements in 10 groups (including 3 XA extreme aspherical elements), Nano AR Coating II
Lens mounts: Sony E-mount (full frame)
Diaphragm Blades: 11 (circular aperture)
Weather resistance: Dust and moisture resistant sealing
Focus drive: 4 XD Linear Motors
Stabilisation: No; relies on SteadyShot IS in camera
Minimum focus: 40 cm
Maximum magnification: 0.17x
Filter size: 72 mm
Dimensions (Diameter x L): 87 x 108 mm
Weight: 778 grams
Standard Accessories: Front and end caps, ALC-SH16 cylindrical lens hood, soft case and strap
Distributor: Sony Australia; 1300 720 07
Based on JPEG images captured with the Sony α7 II camera.
Based on ARW.RAW files recorded simultaneously and converted into 16-bit TIFF format with Adobe Camera Raw.
Vignetting at f/1.2.
ISO 100, 1/200 second at f/11.
ISO 100, 1/8000 second at f/1.2.
Close-up at f/1.2; 1/5000 second at ISO 100.
Highlight outlining in backlit close-up at f/1.2; 1/8000 second at ISO 100.
Sunstar; ISO 100, 1/1000 second at f/16.
ISO 640, 1/60 second at f/11.
ISO 100, 1/320 second at f/2.2.
ISO 100, 1/125 second at f/4.
ISO 100, 1/100 second at f/5.6.
ISO 100, 1/320 second at f/4.5.
ISO 200, 1/60 second at f/5.6.
RRP: AU$2999; US$1999
- Build: 9.0
- Handling: 8.8
- Image quality: 9.0
- Autofocusing: 9.0
- Versatility: 8.7