Fujifilm is working to deliver all kinds of lenses for its medium format mirrorless camera system, including zooms. The Fujinon GF 100-200mm F5.6 R LM OIS WR ($1,999) is one of a pair available now—the other is a 32-64mm—covering angles of view that fall into the short telephoto range. The narrow aperture makes it less versatile, especially when working in dim light, but it's very sharp and optically stabilized,

Narrow F-Stop, but Stabilized

The 100-200mm ($1,499.00 at Amazon) is about the same size and weight as a typical 70-200mm zoom with full-frame coverage—7.2 by 3.5 inches (HD) and 2.3 pounds, with a 67mm front element. The design incorporates a tripod collar, but you can remove it if you don't find it necessary. The collar has its own tripod mount, positioned so it will better balance when used with a tripod or monopod.

It covers a larger, medium format image sensor, so instead of a bright f/2.8 f-stop like the similarly sized Canon EF 70-200mm f/2.8L IS III USM, the lens has a relatively dark f/5.6 diaphragm. Because of the difference in sensor sizes, the GF 100-200mm covers an angle of view closer to a 75-150mm full-frame zoom.

As with other lenses—and cameras—for the GF medium format system, the 100-200mm is protected against dust and splashes. You can feel comfortable pairing the 100-200mm with the GFX 50S or 50R and using it any sort of weather. The lens pairs better with the beefier 50S, though I didn't find it to be too front-heavy when using it with the smaller 50R.

There are three manual control rings on the lens. Manual focus is at the front, zoom in the middle, and the aperture control is closest to the lens mount. It can be set manually from f/5.6 through f/32 in third-stop increments and has an A position for automatic control, and a C position to move the control to the camera body.

There are two control switches on the side, a focus limiter and the on/off control for the optical stabilization system. The limiter allows the autofocus system to lock on over its full range, or on distant subjects only.

The lens incorporates optical stabilization, which is certainly a plus given its focal length and f-stop. Fujifilm doesn't put this into many of its medium format lenses—the 120mm Macro and 250mm F4 are the only other lenses with the feature available for the system. The company does plan on releasing a camera with in-body image stabilization (IBIS) in the future.

Like the 250mm F4, the 100-200mm is compatible with the Fujinon GF 1.4X TC WR Teleconverter. Using it turns the lens into a 140-280mm zoom, but cuts the maximum aperture to f/8. I didn't have the opportunity to try the lens with the teleconverter.

Close focus is available to 23.6 inches (60cm). It offers plenty of flexibility—you'll have no problem framing a tight headshot while maintaining enough distance between you and your subject to sidestep the exaggerated features you can get when working too close. For macro photography, the lens projects images at 1:5 life-size. It's not as large as the 1:2 offered by the 120mm Macro, the only dedicated macro lens on sale for the GF system.

Tack-Sharp Images

I tested the 100-200mm with the 50MP GFX 50R ($4,499.00 at Amazon) . From an imaging perspective it is identical to the 50S. Fujifilm has stated that its GF lenses are designed for future, higher-resolution sensors, and is currently developing a model with a 100MP stabilized image sensor.

See How We Test Digital Cameras

On the current-generation 50MP sensor it puts up outstanding resolution at 100mm f/5.6, resolving 4,937 lines according to Imatest. Performance is, for all practical purposes, dead even from center to edge. You have a little room to stop down and maintain a similar level of resolution—we see 5,038 lines at f/8, 5,241 lines at f/11, and 5,044 lines at f/16. Diffraction reduces clarity at f/22 (4,299 lines) and f/32 (3,048 lines). Results at 150mm are close enough to those at 100mm that they don't bear repeating.

There is a very slight drop in resolution at 200mm. At f/5.6 the lens resolves 4,693 lines. It improves slightly at f/8 (4,874 lines) and is at its best at f/11 (5,098 lines). You can still feel comfortable shooting at f/16 (4,794 lines), but diffraction is an issue at f/22 (4,064 lines) and f/32 (3,030 lines).

The resolution numbers are among the highest we've seen on the GFX 50 image sensor, so it's safe to say the 100-200mm ekes the most quality out of it as possible, even when shot at maximum aperture. We'll test the lens again when a 100MP camera is available to see if the same rings true.

The lens shows no distortion, an accomplishment for any zoom design. Likewise, a vignette is absent from photos. Illumination at the corners is within a stop of the center and the sides are within a half-stop. The narrow aperture certainly comes into play here, as we tend to associate dimmed edges with bright lenses.

Stellar Optics, Unambitious Design

There is absolutely no question about how good of a lens the Fujinon GF 100-200mm F5.6 R LM OIS WR is from an optical standpoint—it's outstandingly sharp, doesn't show any distortion, and is optically stabilized. If you're invested in the GFX system and in the market for this type of lens, you're all set.

But I can't help wish Fujifilm had opted for a brighter design. After all, Pentax has an 80-160mm f/4.5 zoom for its medium format system, and it's designed to cover a 645 film frame, larger than the GFX image sensor.

The 100-200mm is a fine choice for a daytime hike—offering a decent macro capability, a rather light design, and a bit of zoom power. But it's not a lens you'll reach for in dim light. That may not be a concern to you. If you're happy with f/5.6, and want a telezoom for your GFX camera, there is absolutely no reason not to get the 100-200mm. Its image quality won't disappoint in any way.

Best Lens Picks

• The Best Fujifilm Lenses for 2020
• The Best Leica M Lenses for 2020
• The Best Micro Four Thirds Lenses for 2020
• The Best Pentax SLR Lenses for 2020
• More Lens Reviews
• More from Fujifilm

Further Reading

• Tamron Details Affordable 70-180mm F2.8 Zoom Lens
• The Best Sony Mirrorless Lenses for 2020
• The Best Nikon Lenses for 2020
• The Best Canon Lenses for 2020
• Oops! $13K Camera Lens Sells for $95 Due to Prime Day Error