Sony’s New 400mm and 600mm GM Primes Put Super-Telephoto Reach Under One Kilo

A 600mm full-frame autofocus prime that weighs 995 grams, before its tripod foot is attached, sounds like a typo. It is Sony’s published figure for the FE 600mm F6.3 GM OSS, announced on September 15, 2026. The figure gets more interesting when you remember what a 600mm lens is normally for: distant birds, field sports, shy wildlife, subjects you cannot simply walk closer to.

There’s a trade, of course. This is not a 600mm F4, and it does not gather as much light. Sony’s new pair is built around a different promise: bring a serious long lens on the walk, not just to the event. That shift matters as much as the sub-kilogram number.

A super-telephoto you might actually carry

Sony’s new FE 400mm F4.5 GM OSS and FE 600mm F6.3 GM OSS each weigh less than a kilo without their tripod mounts. At a glance:

• 400mm F4.5 – 994g; 108mm in diameter; 242mm long.
• 600mm F6.3 – 995g; 108mm in diameter; 263mm long.

On a camera, these are still unmistakably long lenses, but they look much closer to something you might handhold while looking for a bird than the traditional “great white” prime mounted on a monopod. Sony’s launch release states that both listed weights exclude tripod mounts.

The comparison with Sony’s older flagships shows what changed. The 400mm F2.8 GM OSS weighs 2,895g and the 600mm F4 GM OSS 3,040g. The new 400 and 600 are each about one-third of those weights, depending on which old model you compare. Sony launched the 400 F2.8 in 2018 and the 600 F4 in 2019 as high-speed tools for sports, news and wildlife professionals. The 2026 lenses keep the reach, but ease off the aperture and the burden.

The numbers are the headline; balance may be the part photographers notice after an hour. Sony says it moved the center of gravity closer to the camera body, so a photographer can hold framing, pan and track without the front end constantly pulling down. That claim makes practical sense. Weight at arm’s length is not felt like weight in a backpack. In an early PetaPixel review of the 600mm, Eric Chan wrote, “Sony wanted to make a portable telephoto prime that’s easy to handhold, and the company undeniably achieved it.” That is a reviewer’s first-hand impression, not a guarantee that 995 grams will feel light to every photographer.

There is proper GM engineering inside the small shells, too. Sony lists three Super ED elements and one ED element to control color fringing, Nano AR Coating II to reduce flare and ghosting, an 11-blade aperture for rounded background blur, and two XD linear motors for autofocus. Both lenses have optical stabilization, four programmable focus-hold buttons, a focus limiter, and support for Sony’s 1.4x and 2.0x teleconverters. The front takes 95mm filters. Sony describes the bodies as dust- and moisture-resistant, while its footnote says they are not guaranteed to be fully dust- or moisture-proof.

400mm for movement, 600mm for distance

The 400mm keeps more of the moment

A 400mm lens is long enough to isolate a player or a bird, but it leaves more room around the subject than a 600. That extra context can help: a cyclist cresting a hill, a raptor banking past its nest, a footballer with the defensive line still visible behind. It can also make fast movement easier to follow, especially when a subject comes closer than expected.

Sony press release image, Sony FE 400MM F4.5 GM OSS lens.

The F4.5 maximum aperture is the compromise that makes this package possible. Against a 400mm F2.8, F4.5 gives up a little more than one stop of light. At a poorly lit arena or under thick trees late in the day, that can mean raising ISO or accepting a slower shutter. The new prime’s minimum focus distance is 2.5m, and Sony rates its maximum magnification at 0.18x. Attach a 1.4x teleconverter and it becomes a 560mm F6.3; the 2x converter takes it to 800mm F9. Reach, with the expected loss of light. Sony’s 400mm specifications confirm those numbers.

For most small birds, 600mm has always felt like the perfect focal length. For larger birds and wildlife, 400mm gives me a little more freedom to react and compose
Jared VanderMeer, wildlife photographer

It’s a useful field distinction, though it remains one photographer’s early impression rather than a lab result. The Sony Alpha Universe story identifies him and shows example frames.

The new prime also sits beside a growing range of zoom choices. Sony’s 100–400mm F4.5 GM zoom covers the same long end with framing flexibility, while its 200–600mm F5.6–6.3 zoom spans a wider range at roughly 2.1kg. The 600mm prime is less than half that weight, but fixed at 600mm. In practice, the zoom may be the safer pick when subjects jump around in distance; the prime makes a stronger case when carrying comfort and light are the limiting factors.

The 600mm is for the shot you cannot walk into

At 600mm, a small bird can fill more of the frame from a respectful distance, and an athlete at the far end of the field does not need to be cropped as heavily. Sony gives the new lens a 2.5m minimum focus distance and 0.25x maximum magnification, useful numbers for close encounters with small subjects. Add the 1.4x converter and the lens reaches 840mm F9; the 2x converter makes it 1,200mm F13. Those are specialist combinations, and atmospheric shimmer or poor light can blunt the benefit of extra reach. Still, on a bright morning with a distant bird, the framing possibilities are obvious.

Sony press release image, Sony FE FE 600MM F6.3 GM OSS lens.

Sony says the pair will work with the Alpha 9 III’s burst shooting at up to 120 frames per second with AF/AE tracking. That is a compatibility claim, not a promise that every camera setting, subject or lighting condition will deliver 120 keepers per second. Sony’s own footnote says maximum continuous speed can be lower in some conditions. But the broader point is sound: these are not slow manual-focus novelties. Sony is positioning them for moving birds and sports, where the lens has to keep up with both the camera and the subject. Sony’s launch release adds a note that maximum continuous speed can be lower in some conditions.

The headline, the fine print, and the next test

Confirmed facts: Sony’s specification pages list the models, dimensions and weights above. The “world’s lightest” language is Sony’s claim, and its scope is unusually important. Sony dates its comparison to the September 2026 announcement and defines the 400mm category as full-frame interchangeable super-telephoto lenses that include 400mm and open to F4.5 or faster. For the 600, the cutoff is lenses that include 600mm and open to F6.3 or faster. The advertised weights exclude the tripod mounts. These are confirmed figures on Sony’s spec pages; the global ranking is a company survey, not a universal standard administered by an outside body. The qualification appears in Sony’s official launch notes and on the 400mm and 600mm product pages.

we applied our GM expertise to create the world’s lightest 400mm and 600mm primes in their class
Yang Cheng, Sony’s vice president of Imaging Solutions

The announcement also contains a sales plan, not a record of completed shipments. Sony said European buyers should see the lenses from the end of September, at indicative prices of about €2,800 for the 400mm and €3,900 for the 600mm. Its North American release listed October availability and MSRPs of $2,699.99 and $3,699.99. Prices and delivery windows vary by region; as of September 26, they are still announced schedules. The release did not set a date for any future refresh of Sony’s faster 400mm F2.8 or 600mm F4 lenses.