The FE 400mm f/4.5 G Master OSS is Sony’s long-awaited answer to the über-popular Nikon Nikkor Z 400mm f/4.5 VR S lightweight telephoto lens. Alongside the new FE 600mm f/6.3 GM OSS, the 400mm f/4.5 is also Sony’s first alternative to the Sigma 500mm f/5.6 DG DN Sports. Is the 400mm f/4.5 a strong answer to the competition?

Sony’s two new G Master telephoto prime lenses are, for all intents and purposes, a paired set. The FE 400mm f/4.5 GM and FE 600mm f/6.3 GM are very similar and arrived at the same time, so we have one video review for both.

However, it is unlikely a photographer would buy both new prime lenses instead of picking their favorite. If you’re going to have FE 400mm f/4.5 and FE 600mm f/6.3 prime lenses, which combined cost over $6,000, I’d really have to wonder why you didn’t just buy a telephoto zoom lens.

Sony FE 400mm f/4.5 GM OSS: How It Feels

“More weight” matters here because the Sony FE 400mm f/4.5 GM OSS makes a lot of lofty promises, chief among them professional-grade telephoto performance in an extremely compact, portable form factor. And holy smokes, did Sony ever deliver on that front.

The professional-grade Sony 400mm f/4.5 GM feels impossibly light in the hand. It weighs just 994 grams (2.2 pounds) without its tripod foot attached and is 242 millimeters (9.5 inches) long. It has a 95mm front filter diameter. This is better than a drop-in filter slot as far as I’m concerned, even if 95mm filters aren’t super common.

While this is not a Sony FE 600mm f/6.3 GM review, it is worth pointing out that the only physical difference between the new 400mm f/4.5 and 600mm f/6.3 prime lenses is that the 600mm lens has a longer narrow section at the lens mount, which makes it 21 millimeters (0.83 inches) longer and adds just a single gram (0.03 ounces) to its weight.

So the Sony FE 400mm f/4.5 GM feels very light in the hand. But it also feels solidly built. Making a lightweight lens that doesn’t feel cheap can be a challenging needle to thread, but Sony has pulled it off here.

All the expected G Master accoutrements are present and accounted for. The lens has five switches: AF/MF, Full Time DMF, focus range, OSS On/Off, and OSS mode. The lens has Sony’s classic silver name plate, which gives it an air of class. It has some engraved markings, Sony’s cinnabar G Master badge, and a rotating tripod collar. The tripod collar can’t be removed, but the tripod foot can.

Speaking of the tripod foot, it’s really the only major area of complaint I have about the design and handling of Sony’s new telephoto primes. I have said it before, I’ll say it now, and I’ll undoubtedly say it again the next time Sony releases a lens with a tripod foot: Please make it Arca-Swiss compatible. It’s a small physical change, but it offers huge quality-of-life benefits. Having to attach a dedicated tripod plate to the lens, rather than slotting the lens directly into a tripod head, is an annoyance I don’t think any of us should still be facing in 2026.

But I digress. One more area where I think the FE 400mm f/4.5’s design leaves something to be desired. The focus ring is well-positioned, generously large, and grippy, but it also feels a bit loosey-goosey under hand. While I rarely needed to manually focus the lens while shooting, when I did, the experience was a bit frustrating. I want the focus ring to feel more precise and offer more resistance.

The lens has four customizable Focus Hold buttons, a customizable Function Ring, and a nice removable lens hood.

All that said, the Sony FE 400mm f/4.5 GM OSS is well designed, impressively compact and lightweight, and I have the utmost confidence that it will survive professional workflows in harsh situations for years to come.

Sony FE 400mm f/4.5 GM OSS: How It Shoots

The Sony FE 400mm f/4.5 GM OSS has 22 elements arranged across 16 groups in front of an 11-bladed aperture. The resulting image quality is outstanding. As a G Master lens, the 400mm f/4.5 has all the advanced optical technology you would expect, including Super ED and ED elements and Nano AR Coating II.

Again, this isn’t the 600mm lens review, but that lens is optically nearly identical, except for an extra two elements in a single extra group near the lens mount. I’m just pointing that out.

From an optical performance perspective, the 400mm f/4.5 GM leaves very little to be desired. The lens is extremely sharp when shooting wide open and delivers pleasing, clean bokeh. While the 400mm and 600mm primes are too long to evaluate on our test charts, it’s pretty obviously a supremely sharp lens in real-world testing. It’s objectively a high-resolution lens.

Bokeh is much more subjective, though there are a few things we look for. Is the bokeh clean? Quite. Is it perfectly circular? Not quite, but it’s close. Of course, I personally like a bit of cat’s-eye effect in my bokeh, but I know it’s not everyone’s cup of tea.

For typical 400mm lens situations, like sports and wildlife, I think the bokeh will be sufficiently pleasant to the eye. If your subject is far away and relatively close to your background, the 400mm f/4.5 GM won’t wash the background in beautiful softness like a 400mm f/2.8 lens will, but it can still render backgrounds significantly softer and less distracting.

There are really no image quality issues here. So what about other aspects of shooting performance, like autofocus? Well, thanks to a pair of XD (extreme dynamic) and a single XD Linear Motor, the 400mm f/4.5 GM focuses extremely quickly. It is fast, precise, quiet, and smooth.

I don’t love its minimum focusing performance, though. With a minimum focus distance of 2.5 meters (8.2 feet), the lens delivers maximum magnification of just 0.18x, which is fine but not great. There were quite a few times when I had to slowly back up to focus on the subject, which is tedious.

While I didn’t use the FE 400mm f/4.5 GM with any teleconverters, it can take both of Sony’s options, the 1.4x and 2x TCs. With the 1.4x teleconverter attached, the Sony FE 400mm f/4.5 GM acts like a 560mm f/6.3 lens. With the SEL20TC (2x) attached, it is an 800mm f/9 equivalent. 800mm f/9 is pretty slow, but it’s nice to have that flexibility.

Overall, the Sony FE 400mm f/4.5 GM shoots extremely well. Its image quality is top-notch, the bokeh is pleasing, and the autofocus is excellent.

Who Should Buy the Sony 400mm f/4.5 GM OSS?

The Sony FE 400mm f/4.5 GM OSS is an interesting lens. It is very good and easy to recommend in a vacuum. However, it faces some seriously stiff competition.

On its own, and ignoring the competition, the FE 400mm f/4.5 GM is a very good lens for sports photographers. Although I haven’t had a chance to shoot sports with it, I’ve shot enough sports to know how good the 400mm focal length is for outdoor sports like baseball, football, and soccer. It’s a popular focal length for a reason.

While f/4.5 is not as impressive as f/2.8, the tradeoff here is that you get a compact, lightweight lens that is very easy to handhold not just for a quarter but an entire game. That has value.

The Sony FE 400mm f/4.5 GM is a much tougher sell for wildlife photography. 400mm is a good focal length for some animals, like larger mammals, but a challenging lens to use for bird photography. Yes, I did it, but I was basically at the lens’s minimum focusing distance to effectively fill the frame with a bird and good luck getting that close most of the time.

A somewhat underrated use of telephoto lenses is landscape photography. I think the Sony 400mm f/4.5 GM can do well here. However, I question why someone would opt for a prime for that purpose rather than something like the Sony 100-400mm f/4.5-5.6 GM OSS or, if you’re feeling like spending $4,300, the FE 100-400mm f/4.5 GM, which has the same aperture and an extra 840 grams but way more versatility.

It’s hard to find a situation where the Sony FE 400mm f/4.5 GM is the obvious “best choice,” and that’s more because of the incredible options on E-mount than any deficiency with the lens itself. I think you really need to value the 400mm f/4.5’s portability to make it the right lens for you.

If the Sony FE 400mm f/4.5 GM ticks the right boxes for you, then it will not disappoint. It’s a great lens.

Are There Alternatives?

This should be clear by now, but yes, there are some very good alternatives.

On the first-party side, there’s the Sony FE 100-400mm f/4.5-5.6 GM OSS ($2,800), which offers the same reach with a slightly slower aperture. You get the versatility of a zoom lens, which has serious value for some photographers. The 100-400mm f/4.5-5.6 GM OSS is about 400 grams heavier, and although shorter at its smallest size, it extends as you zoom.

Then there’s the new FE 100-400mm f/4.5 GM. This is in a slightly different price range, of course, setting photographers back $4,300. However, it offers the same benefits as the older 100-400mm GM zoom, with a faster f/4.5 aperture at 400mm. Frankly, it’s one of Sony’s most impressive lenses to date. It’s outstanding. It is 328 millimeters (12.9 inches) long and weighs 1,840 grams (four pounds), so it’s bigger and heavier, though it remains easy to handhold.

It’s safe to say the new FE 600mm f/6.3 GM is another option. Both are great, so it comes down to which focal length and aperture combo you want more. There are reasons to go for either.

I think it’s also fair to consider Sony’s 200-600mm f/5.6-6.3 G OSS a legitimate competitor to its new 400mm f/4.5 prime lens. The 200-600mm is $2,100, so it’s cheaper than Sony’s new 400mm f/4.5 prime lens. However, the 200-600mm zoom is much bigger and heavier, weighing over twice as much. Having owned a 200-600mm for a long time, I can also safely say it’s not as optically impressive as Sony’s new 400mm f/4.5 GM lens.

On the third-party side, the most obvious competition to the Sony FE 400mm f/4.5 GM is the Sigma 500mm f/5.6 DG DN OS Sports. It’s currently $2,999 with a $300 instant savings, so it’s similarly priced. It is longer (236.6 millimeters / 9.3 inches) and heavier (1,400 grams / three pounds) than Sony’s new lens, but still impressively compact and lightweight overall. It delivers excellent image quality, very good autofocus, and a similar maximum magnification (0.17x). However, unlike Sony’s first-party lenses, the Sigma 500mm f/5.6 can’t shoot faster than 15 frames per second with continuous autofocus, which could be a dealbreaker for some professional sports and wildlife photographers.

Should You Buy It?

Yes. If the Sony 400mm f/4.5 GM OSS addresses your needs, you can’t really go wrong with it. While I do think the utility of a 400mm f/4.5 lens is a bit narrow, there’s no question that the Sony FE 400mm f/4.5 G Master is an excellent lens.