Fujifilm has announced the XF 400mm f/4.5 R LM OIS WR, and the number that matters is not the focal length but the weight. At 1,245g this is a super-telephoto prime you can genuinely hand-hold through a day in a hide, and on APS-C it delivers a 609mm equivalent field of view. Full details are on Fujifilm’s site.

Why 1,245g is the headline

Super-telephoto primes have traditionally meant a monopod at minimum and a tripod in practice. Canon’s RF 400mm f/2.8L weighs nearly three kilos; the general assumption with this class of lens is that you are supporting it rather than holding it.

At 1,245g the XF 400mm changes that calculation. That is roughly the weight of a 70-200mm f/2.8 on full frame, and it means walking a coastline, following a raptor or working a motorsport paddock without carrying support you then have to set up every time something happens. For wildlife photography in particular, where the shot is usually gone before a tripod is level, that matters more than a stop of aperture would.

Fujifilm quotes 5.5 stops of stabilisation from an optimised mechanism with improved shake detection, which is what makes hand-holding at 609mm equivalent realistic rather than theoretical.

The optics and the reach

The optical formula runs 21 elements in 14 groups, including two Super ED and four ED elements to control chromatic aberration — which is the perennial problem at this focal length, where colour fringing on a bird against a bright sky is immediately obvious. Fujifilm claims some of the highest optical performance in the entire XF line.

The aperture is nine rounded blades running from f/4.5 to f/22, and minimum focus is 2.75m for a maximum magnification of 0.16x. There is a focus limiter that prevents hunting closer than 5m, which speeds up acquisition considerably on distant subjects.

Teleconverter support is where it gets interesting. The XF1.4X TC WR takes it to 560mm, a 853mm equivalent; the XF2X TC WR reaches 800mm, or 1,219mm equivalent. That is genuinely long, and it arrives without the bulk a native lens at that reach would demand.

Built for weather

There are 20 sealed points on the barrel, with operation rated to -10°C and a fluorine coating on the front element to repel water and resist smudging. The filter thread is 95mm, and the tripod foot is removable — sensibly cut with Arca-Swiss dovetails, so it drops straight onto a head without an additional plate. There is a full aperture ring, focus range limiter and preset focus controls.

Fujifilm notes that this completes its super-telephoto prime range, which now covers roughly 300mm to 762mm equivalent.

Our take

This is a significant addition for X-mount, and it fills a real gap. Fujifilm’s wildlife and sports credentials have rested on zooms and the XF 500mm, and a lightweight 400mm prime sits exactly where a great many photographers actually work.

The price is the sticking point. At £2,499 this is professional money, and for that outlay you are choosing the X system deliberately rather than by default. The counter-argument is the crop factor: getting to 609mm equivalent on full frame means a 600mm lens, and those cost considerably more and weigh at least twice as much.

For anyone already invested in X-mount who shoots birds, motorsport or aviation, this looks like the lens the system has been missing.

Fujifilm XF 400mm f/4.5 R LM OIS WR: Specifications

Mount: Fujifilm X. Focal length: 400mm (609mm equivalent in 35mm format). Maximum aperture: f/4.5; minimum f/22. Optical construction: 21 elements in 14 groups, including 2 Super ED and 4 ED elements. Aperture blades: 9, rounded. Stabilisation: up to 5.5 stops optical. Autofocus: linear motor. Minimum focus distance: 2.75m; maximum magnification 0.16x. Focus limiter: yes, restricting focus beyond 5m. Filter thread: 95mm. Dimensions: 104.5 x 239.5mm. Weight: approximately 1,245g. Weather sealing: 20 sealed points, operation to -10°C; fluorine-coated front element. Tripod foot: removable, with Arca-Swiss dovetails. Teleconverter support: XF1.4X TC WR to 560mm (853mm equivalent); XF2X TC WR to 800mm (1,219mm equivalent).

Fujifilm XF 400mm f/4.5 R LM OIS WR: Price and availability

The XF 400mm f/4.5 R LM OIS WR is priced at £2,499 in the UK ($3,199.95 US / CA$3,899.99 / AU$4,949), with availability from mid-September 2026. Pre-orders are open at major retailers.