Yasuyuki Nagata, Head of Sony's global Interchangeable Lens business, pictured at the press event where US journalists got our first look at the new G Master 600mm F4.

We were in New Jersey recently, for the unveiling of two new Sony lenses - the G Master 600mm F4 OSS, and the more enthusiast-focused 200-600mm F5.6-6.3 G OSS. During the event, we spent some time with Yasuyuki Nagata, head of Sony's global interchangeable lens business, to discuss the new products, and Sony's approach to mirrorless lens development.

These products use technologies developed for the 400mm F2.8 - how has that product performed in the market?

The sales have been much higher than we expected - more than double. We thought at the first stages of development for the lens that there were only a few people who would shoot sports with our products - for example only Alpha 9 users, or photographers who shoot smaller small sporting events. But after we launched the 400mm, we have seen demand from many of the top sports photographers working at large events.

Do you have a sense of how many professional photographers are using that lens, versus enthusiasts?

Almost 70% of the [customer base] for that lens are professionals. Availability is still capped - there is a long waiting list.

Who do you see as the target market for the new lenses?

Compared to the 400mm, the 600mm is more targeted at high-end amateurs. Photographers that shoot birds, wildlife, aircraft. Maybe 70-80% will be wildlife photographers. That’s why the market is bigger for the 600mm than the 400mm.

The 200-600 will appeal to the same audience [to some extent] but some people who use those kinds of lenses will use them with APS-C cameras. To get more reach.

The new GM 600mm F4 is a big lens, but it's the lightest in its class, coming in at just 10g less than the similarly-styled Canon EF 600mm F4 III

What are the specific differences between the two new lenses that account for the difference between ‘G’ and ‘GM’?

With G Master lenses we always include the latest, innovative technologies. We never compromise. Always the latest technologies. With the 200-600mm, there are some compromises, for example in the materials, or the body. We didn’t use magnesium-alloy, or the [newer XD linear autofocus] actuator.

The key concept is ‘future lenses for today’

Affordability is also important for the G series, to expand the size of the market. And sometimes it’s practicality. We don’t actually need to use the XD linear actuators with a small focusing group for example [like the one in the 200-600mm].

What were the major priorities for the design of the 600mm?

Basically we’re targeting the best of the best. Without compromise. Every time we plan to make a G Master series lens, we aim for 'no competition'. Which means the highest spec. We don’t compromise on anything. Autofocus, image quality, light weight. What I mean by that is we develop new technologies every time. So there’s not a particular standard for G Master, we just include innovative technologies every time. Technologies that didn’t exist before.

We’re always listening to our professionals. And after we launched the 400mm, a lot of professionals told us they wanted a 600mm. We also consider camera bodies that will come in the future as well. The key concept is ‘future lenses for today’.

All of the main controls on the 600mm F4 are the same size, and in the same position as those on the 400mm F2.8. This is deliberate, and intended to make it as easy as possible for photographers to use the lenses alongside one another at events.

So when you’re designing a lens like this are you planning for even more focus calculations per second and faster frame rates than the a9 can achieve, for example?


If we assume that this is a lens that will be used by a lot of a9 photographers, what kind of camera do they want next?

They always request more speed, less weight, greater usability. I think that every professional photographer wants something different. We gather all those voices and we use that feedback to plan what we should do.

When you develop a lens like the 200-600mm, how important is the requirement for video shooting?

It must support video functions. Convergence from the video side is a very obvious trend, even in the US market. That’s why we use linear action autofocus actuators. Part of it is mechanics, and part of it is optics.

The integration with our camera bodies is much better than our competitors

In zooms we’re always trying to reduce focus breathing for example, and axial shift. All of the characteristics in zooms which [can] make it a challenge to use them for video.

How would you summarize the competitive advantages of these new lenses compared to existing products on the market?

If you shoot seriously, the 600mm is for you. The spec of the lens itself, its weight and its resolution is perhaps almost the same [as the current best competitive alternative]. But the integration with our camera bodies is much better than our competitors, I think. So if photographers want to maximize the performance of their camera body, they should use this lens. At this moment, there is no competition to the Alpha 9. Its performance is the best.

The 200-600mm is a more comfortable lens to carry, at a reasonable price. We want many customers to use the 200-600mm. And we made it compatible with our tele-converters. We want to expand that field.

The 200-600mm F5.6-6.3 is a pretty long lens, but a lot of that length is the removable hood. Unlike most lenses of its kind though, the zoom is internal, so it doesn't get longer when zoomed in.

How much difference does the body make to lens focus performance? For example if someone is using a first generation Sony Alpha 7, how different will their experience of this lens be to someone using an a9?

It will be a totally different experience. We’re always saying that we try to see the future of cameras, and this lens is capable of much [faster] performance than the current specs of the a9. So this lens will be able to keep up with the next generation. It has much more potential [than the specifications of the current generation cameras].

Is the speed of electronic communication between the camera and lens a big part of that?

Yes. We hear some manufacturers talking a lot about the number of channels of communication between camera and lens, but if the autofocus actuators in the lens can’t keep up, it doesn’t matter.

The biggest challenge is keeping the size and weight down

When we design lenses we’re always thinking about the camera bodies. Compatibility between the mechanical parts, electrics, even software. These lenses are designed specifically for our mirrorless cameras.

What are the major challenges in making such a small, lightweight lens with such a fast autofocus actuator?

The biggest challenge is keeping the size and weight down. The optical components are determined largely by [the constraints of] optical physics. There aren’t any magic technologies to reduce the size of optical elements, and the diameter of the elements can’t be reduced because it determines the F number. The electronic parts on the other hand, like the autofocus unit, we can introduce innovative technologies which make the difference. Size and weight is the most difficult thing.

This schematic shows the weight distribution of the previously-released 400mm F2.8 compared to the last-generation 500mm F4 for the DSLR A-mount. The new 600mm F4, like the 400mm, concentrates is weight towards the center-rear of the lens, which helps a lot when shooting with a monopod or for hand-held work.

What does Sony need to do with its optical lineup to become the number one manufacturer in terms of sales?

I can’t disclose future plans, but there are a lot of opportunities, both on the telephoto side and the wide-angle side. Every segment of the lineup, there are opportunities to expand.

What is the attachment rate for teleconverters with the 400mm F2.8?

It’s at least 10%. Teleconverter compatibility was a big priority with these new 200-600mm and 600mm lenses.

Clearly the GM line is where the premium technologies are introduced - will they filter down into consumer products?

It’s possible, depending on timing. Over time we’ll introduce new technologies, and then the [existing] technologies will cascade down, one by one. Lenses are on the market for a long time, not like bodies which can launch every couple of years. But lenses it’s easily more than five years. It’s very hard to compare the camera and lens markets.

You talk about these lenses as being designed for the next generation of cameras - how long do you think these lenses will stand as benchmark performers?

Much longer [than camera bodies], I think maybe about 10 years.

Editor's note: Barnaby Britton

When I last spoke to Mr. Nagata in 2017, he spoke of the increasing importance of professional photographers to Sony, and his 'dream' of seeing Sony cameras and lenses at the Tokyo Olympics in 2020. With the new G Master 600mm F4, he and his designers have taken one step further towards that goal, providing a lens which - like the G Master 400mm F2.8 - represents an almost symbolic position in any 'serious' camera system's lens portfolio. It's clearly very important to Sony that the brand is taken seriously by professional sports and wildlife photographers, and with lenses like these - and cameras like the all-powerful a9 the company is making a very strong case.

In my opinion, the a9 is the most effective camera on the market today for shooting sports. A lot of people will argue the point, but I think the technical evidence, if you care to go looking for it, is clear. That doesn't mean that overnight, professionals will ditch their Canon and Nikon gear for Sony, of course. Without the lenses - and the professional service support - that they need, the a9 is little more than a curiosity. According to Mr Nagata, the entire concept of the G Master lens lineup is 'future lenses for today'. This means two things. Firstly, that the lenses should offer the kind of image quality which won't look out of date in a number of years, and secondly, that they'll be able to keep up with - and take advantage of - future Sony camera technologies.

Older D/SLR lenses were not designed for 20fps capture using on-sensor phase-detection autofocus

The a9 is a seriously powerful camera, capable of communicating with compatible lenses at a rate of sixty times per second, but at some point it will be replaced by something even more powerful, with a higher sensor resolution, and capable of even greater performance. A lens like the G Master 600mm F4, with its twin high-speed 'extreme dynamic (XD)' linear focus motors, has to be designed with this kind of development in mind.

While Mr. Nagata is perfectly candid that in terms of image quality and basic specs alone, it might look similar to existing lenses from other manufacturers (the newest version of Canon's EF 600mm F4 being the most obvious reference point), those older D/SLR lenses were not designed for 20fps capture using on-sensor phase-detection autofocus. 'No competition' indeed...

Slightly further down the lineup, the 200-600mm F5.6-6.3 is a more mass-market lens. Despite its lower positioning, it's actually likely to be more important to, and more widely used by, enthusiast photographers and DPReview readers. It's not a small lens, but the internal zoom and focus keep it relatively compact when out and about, and in my experience of shooting with it, the versatility - and sharpness - is impressive. This is the kind of lens that Sony has to release, in order to 'expand the size of the market' and hit Canon and Nikon where it hurts - in the high-end enthusiast market segment.