| Product photos: Mitchell Clark |
Sony has announced the FE 100-400mm F4.5 GM OSS, a full-frame telephoto lens that acts as a spiritual successor to the 100-400mm F4.5-5.6 GM OSS from 2017. Of course, there are a few differences; it now features a constant maximum aperture, as well as an internally zooming design, though both things come with a cost (and not just a monetary one).
The 100-400mm F4.5 GM OSS is made up of 28 elements in 20 groups, using a mix of Sony’s advanced optics. That includes two “Super ED” and three ED elements to reduce chromatic aberration, an “XA” aspheric lens and an “ED XA” (extra-low dispersion extreme aspherical) lens to suppress aberrations and reduce onion ringing in bokeh. It has an 11-bladed aperture, and a minimum focusing distance of 0.64m (2’1″) at the wide end, and 1.5m (4’11”) at the long end.
It uses four of Sony’s “XD” linear autofocus motors, which the company says will provide responsive tracking even when using the a9 III’s 120fps burst mode. It speaks to the ambition of making a lens that’s perfectly capable of shooting sports and wildlife. To that end, it can also be fitted with a teleconverter for extra reach.
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| There are a lot of controls on this lens (plus an extra one on the other side of the foot, hidden by a door). |
The 100-400mm F4.5 GM OSS has all the other bells and whistles you’d expect from this grade of lens, too. A bank of switches along the side let you control things like autofocus / manual focus, Sony’s “Full Time DMF” feature, applying a focus limiter, turning optical stabilization on and off, and choosing which mode it’s in. It also features four customizable buttons; they’re all assigned to the same function, but give you quick access no matter how you’re holding the lens. Behind them is a toggle function ring, and then the zoom ring, which has adjustable tension, and only requires a quarter turn to go from 100 to 400.
The rotating tripod foot – which is quite comfortable to hold thanks to its dual-texture design – has detents at 90° intervals, which you can set to be clicked or click-less. Finally, Sony has a solution for anyone who balks at buying 95mm filters for this lens: near the mount is a drop-in filter holder, which can accommodate (much cheaper) 40.5mm glass. The lens is sealed for dust and moisture, and has a fluorine coating on the front element to repel oils, dirt and water.
At 328mm (12.9″), the lens is a fair bit larger than the previous 100-400, which had an extending design and was 205 mm (8.1″) long at its shortest. It’s also heavier, weighing 1840g (64.9oz), versus 1495g (52.7oz). While that’s certainly not nothing, in my experience, it actually feels shockingly light given its size and specs. I was able to carry it around a wildlife area for two hours, often pointing it into the sky to take pictures of birds, without wearing my arms out. It’s also not immensely difficult to carry in a backpack, though it still physically takes up a fair amount of space.
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Unlike Sony’s previous-gen 100-400, you can shoot at F4.5, even at 400mm. Sony a7R VI | Sony FE 100-400mm F4.5 GM OSS | 400mm | F4.5 | 1/400 sec | ISO 320 Out of camera JPEG |
This lens is a more ambitious offering than its nine-year-old predecessor, both in terms of its aperture and its optical performance. It’s clear Sony is targeting professionals and enthusiasts who are shooting sporting events (like the upcoming World Cup) and wildlife, but who want the versatility of a zoom and don’t want to step all the way up to its highest-end telephoto primes. Those users will likely be willing to put up with the fact that the lens is larger and heavier for its speed at the long end, image quality and faster AF.
However, the lens is also coming in at a substantially higher price point than its predecessor, retailing for $4300, while the 4.5-5.6 will run you $2800. Still, for those who need the performance, Sony has clearly built a very capable option. It’ll be available starting in June, alongside the newly announced a7R VI.
Sample Gallery
Please do not reproduce any of these images on a website or any newsletter/magazine without prior permission (see our copyright page). We make the originals available for private users to download to their own machines for personal examination or printing; we do so in good faith, so please don’t abuse it.
While we typically process images for a lens sample gallery using Capture One, we used the Sony a7R VI to test the lens, which isn’t currently supported by that program. The images are out-of-camera JPEGs, and will therefore have corrections applied. We’ll look to replace them with processed Raws when we can.
Press release:
Sony Electronics Unveils the FE 100-400mm F4.5 GM OSS G Master™
Super-telephoto zoom with constant F4.5 aperture, autofocus up to 3x faster1,2, and outstanding mobility
SAN DIEGO, May 13, 2026 — Sony Electronics Inc. introduces the FE 100-400mm F4.5 GM OSS, the newest addition to its flagship G Master™ lens series for full-frame AlphaTM E-mount cameras. Covering a 100-400 mm focal range with a constant F4.5 aperture, the lens delivers the exceptional resolution and bokeh that define the G Master series, high-precision autofocus (AF) up to approximately 3x faster1,2 than the FE 100-400 mm F4.5-5.6 GM OSS. Weighing approximately 65 oz. (1,840 g) with an internal zoom structure, its stable weight balance offers highly mobile shooting capabilities. The FE 100-400mm F4.5 GM OSS gives wildlife, birding, sports, and photojournalism creators the speed, reach, and image quality to capture decisive moments in any environment, expanding their creative possibilities.
“Our creators want super-telephoto reach with G Master optical quality in a body light enough to shoot handheld all day. The FE 100-400mm F4.5 GM OSS delivers constant F4.5 aperture, dramatically faster autofocus, and a build that keeps up with the user’s instincts, whether tracking a bird in flight or working the sideline at a championship match,” said Yang Cheng, Vice President of Imaging Solutions, Sony Electronics Inc.
Uncompromising G Master Optics
- Resolves fine detail across the full 100-400 mm zoom range, even wide open at F4.5
- Optical design featuring newly developed ED XA (Extra-low Dispersion extreme aspherical), XA (extreme aspherical), two Super ED (extra-low Dispersion), and three ED glass elements, effectively controlling multiple aberrations including chromatic and spherical aberration to achieve exceptional resolution from center to edge across the entire zoom range
- Nano AR Coating II reduces ghosting and flare for high-contrast results in backlit conditions
- 11-blade circular aperture with precision spherical aberration control produces the signature G Master bokeh
- Constant F4.5 maximum aperture eliminates exposure shifts while zooming
- Compatible with optional teleconverters3 for focal lengths up to 800 mm or 1,200 mm in APS-C mode4
Autofocus That Keeps Pace with the Action
- Four custom-optimized XD (extreme dynamic) Linear Motors, a floating focus mechanism, and the latest AF algorithms deliver AF speeds up to 3x faster1,2 with approximately 50 % improved subject tracking2
- Fully compatible with Alpha 9 III continuous shooting at up to 120 fps5 with AF/AE tracking
Lightweight Build, Exceptional Mobility
Combining the latest optical design, mechanical engineering with lightweight yet robust magnesium alloy barrel components, and high-efficiency, high-thrust XD Linear Motors, the lens achieves a lightweight and robust body at approximately 65 oz. (1,840 g)
Inner-zoom design maintains constant length and stable center of gravity throughout the zoom range for precise framing adjustments without shifting balance
Professional-Grade Control and Reliability
- Built-in stabilization supports Active Mode and coordinates internal stabilization control on compatible bodies
- Supports the camera body’s breathing compensation6, correcting angle-of-view shifts during focus adjustments in video recording
- Four focus hold buttons7 and a dedicated function ring for intuitive, personalized operation in the field
- Dust and moisture resistant design8 with fluorine front-element coating maintains reliable performance in challenging conditions
Pricing and Availability
The FE 100-400mm F4.5 GM OSS will be available in June 2026 for approximately $4,299.99 USD and $5,599.99 CAD. It will be sold directly through Sony and various Sony authorized dealers throughout North America.
The FE 100-400mm F4.5 GM OSS product video can be viewed here: https://youtu.be/iDhbKSdqqb8
For more information, visit: https://electronics.sony.com/imaging/lenses/all-e-mount/p/sel100400mc
1 Compared to the FE 100-400 mm F4.5-5.6 GM OSS.
2 When mounted on the Alpha 9 III. Compared to the FE 100-400 mm F4.5-5.6 GM OSS. Based on Sony test conditions.
3 Compatible with 1.4x Teleconverter (SEL14TC) and 2x Teleconverter (SEL20TC).
4 With 2x Teleconverter (SEL20TC) attached.
5 Based on Sony test conditions. Continuous shooting speed may decrease depending on shooting conditions. When focus mode is set to AF-C, continuous shooting speed varies depending on the lens attached. Please check the lens compatibility information support page for details.
6 Please refer to support information for compatible cameras. When this function is set to [On], angle of view and image quality may change slightly. Depending on the lens, compensation may not be fully effective even when this function is set to [On].
7 Assignable functions vary depending on the camera used. Please refer to support information for compatible cameras for details.
8 The lens is designed with dust and moisture resistance in mind but is not completely sealed against dust or water droplets.
Sony FE 100-400mm F4.5 GM OSS specifications:
| Principal specifications | |
|---|---|
| Lens type | Zoom lens |
| Max Format size | 35mm FF |
| Focal length | 100–400 mm |
| Image stabilization | Yes |
| Lens mount | Sony E, Sony FE |
| Aperture | |
| Maximum aperture | F4.5 |
| Aperture ring | No |
| Number of diaphragm blades | 11 |
| Optics | |
| Elements | 28 |
| Groups | 20 |
| Special elements / coatings | 2 super ED, 3 ED, 1 ED XA, 1 XA |
| Focus | |
| Minimum focus | 0.64 m (25.2″) |
| Maximum magnification | 0.25× |
| Autofocus | Yes |
| Motor type | Linear Motor |
| Full time manual | Yes |
| Focus method | Internal |
| Distance scale | No |
| DoF scale | No |
| Physical | |
| Weight | 1840 g (4.06 lb) |
| Diameter | 120 mm (4.72″) |
| Length | 328 mm (12.91″) |
| Sealing | Yes |
| Colour | White |
| Zoom method | Rotary (internal) |
| Power zoom | No |
| Filter thread | 95 mm |
| Filter notes | 40.5mm rear drop-in filter |
| Hood supplied | Yes |
| Tripod collar | Yes |