The cameras in Fujifilm's medium format GF mirrorless lineup are built around big image sensors—they're larger all around than full-frame alternatives and, as such, typically require lenses with a bit more glass. That rule is especially true for optics with bright apertures, such as the Fujinon GF 80mm F1.7 R WR ($2,299), which is a heavyweight prime even among its peers. Its autofocus system is disappointing—you can easily hear the motor and the drive isn't quite smooth—but the lens earns its keep by blurring backgrounds away into nothing. For this reason and its impressive sharpness, portrait specialists and bokeh fiends might be interested enough to look beyond any shortcomings.

F1.7 Optics Make for a Big Lens

The Fujinon GF 80mm is a hefty prime—it's a bit squat and packs a ton of optical glass. The lens weighs about 1.7 pounds and is only slightly taller than wide at 3.9 by 3.7 inches (HD). I paired it with the GFX100S and GFX50S II for testing and found it to be a little heavy for handheld work, but still manageable.

It's by no means the heaviest prime for the system, either. The GF 110mm F2 R LM WR weighs 2.2 pounds, but its tighter angle of view positions it firmly as a specialty lens that you're more likely to break out for a portrait session than use as a daily driver. The GF 80mm captures a wider angle and some may treat it as a standard prime—its view matches a 60mm on full-frame—especially if the shallow depth of field look matches your style.

One complication of those heavyweight optics is that the lens requires some effort to lock in on a subject. The GF 80mm captures a tiny sliver of the world, but the F1.7 focuses with a bit more noise and hesitation than typical, even with a phase detect focus camera. This takes away some of its appeal as an everyday prime. Fujifilm has a few slimmer primes that make more sense for that purpose; for example, you can pick among the GF 63mm F2.8, GF 50mm F3.5, or GF 45mm F2.8 and enjoy a lighter prime with quick, quiet focus.

A metal barrel and extensive weather protection highlight Fujifilm's quality construction. You can comfortably use the lens in all sorts of inclement weather. Anti-smudge fluorine coats its front element, while the bundled hood offers some extra protection from bumps, stray fingerprints, and flare. A 77mm filter thread lets you use a glass filter with the lens.

Two main controls sit on the lens, including an aperture control ring closer to the mount and a large manual focus ring that occupies the bulk of the surface area. Both feature a ridged texture for a ready grip, but while the focus ring is rubberized, the aperture ring is bare metal.

On-lens aperture control is available from f/1.7 through f/22 in third-stop increments—the ring clicks when you turn it. There's also an A position for automatic adjustment and a C position to move aperture control to the camera body. The latter is useful for videographers who prefer Fujifilm's on-screen Silent Movie Control interface—you can't de-click the ring for silent operation.

Manual focus control is a little disappointing. Like most made-for-mirrorless lenses, the GF 80mm focuses by wire—turning the focus ring engages the autofocus motor, as opposed to a mechanical linkage. It makes for a slight lag; I noticed a barely perceptible hesitation between when I turned the ring and heard the focus motor engage.

Focus adjustments also show a breathing effect—the angle of view is noticeably narrower when you focus close versus at a distance. We don't expect a lot of videographers to choose a medium format camera, but if you are one of those few, using the GF 80mm for focus racks requires a bit of care.

Bright lenses aren't usually great for macro, and that rule of thumb rings true here too. The GF 80mm focuses as close as 2.3 feet (70cm) for 1:6.7 reproduction. You won't do much better with any of the standard angle GF primes, but the GF 35-70mm F4.5-5.6 WR is an alternative if you want an everyday zoom with 1:3.6 macro focus.

GF 80mm F1.7: In the Lab

I paired the GF 80mm F1.7 with the 100MP GFX 100S and Imatest software to check its resolution. The lens is very sharp—it hits excellent marks (6,400 lines) wide open. From f/5.6 through f/11, the resolution is outstanding, and nearly as good as you can expect from the GFX100S.

The aperture narrows down to f/22, but images lose contrast at settings smaller than f/11. The blades close down to a tiny circle at those settings and are small enough to scatter light particles as they pass through.

The aperture blades are round, a common feature in modern optics, so the lens is capable of circular highlights at moderate apertures. The GF 80mm F1.7 draws its blurriest backgrounds at f/1.7, but you see some cat eye shapes in the background, especially toward the edges and corners. The highlights are a bit rounder at f/2 and perfectly circular by f/2.8.

Some aspects of the bokeh aren't ideal though—false color rears its ugly head in some instances, for example. You can see purple and green halos in transitions from in-focus to out-of-focus areas, or longitudinal chromatic aberration (LoCa). Save for swapping to black-and-white, you can't do much to sidestep this issue and it's difficult to suppress in Raw processors.

Other optical pitfalls, such as distortion and dimmed corner illumination, aren't big issues here. In-camera corrections compensate for a slight vignette, visible in uncorrected photos through f/2, and remove some slight pincushion distortion. For Raw processing, Adobe Lightroom Classic includes a one-click correction profile for the lens.

Pushes Medium Format Bokeh to the Limit

A bright f-stop sets the Fujinon GF 80mm F1.7 R WR apart from other medium format lenses, and its standard angle view makes it a bit more versatile than the GF 110mm F2 R WR as an everyday prime. Some caveats remain—the GF 80mm is heavy for a prime, not the quickest or quietest to lock focus, and its optics show some LoCa, an effect we don't expect to see in high-end photo gear.

These drawbacks aren't dissimilar to Fujifilm's show-off lens for its APS-C mirrorless system, the XF 50mm F1.0 R WR, another envelope-pushing entry. It's only with the full-frame format that we've seen lenses that manage an ultra-bright design and speedy focus—the Sony FE 50mm F1.2 GM is the best example.

A Sony lens won't do GFX owners much good, though. If you're invested in the system, the GF 80mm F1.7 R WR is the lens to get if you're a fanatic for bokeh and prefer a view that's closer to standard than telephoto. We continue to recommend the GF 110mm F2 as our Editors' Choice for portrait specialists using the GFX system, however.