The Sony FE 135mm F1.8 GM ($2,099.99) is another entry in the company's top-end line of lenses, the G Master series. As with other G Master lenses, the 135mm F1.8 is built to professional specifications, with exotic lens elements, weather-sealed construction, and exceptional resolution. Its focal length makes it a bit of a specialized tool for portraiture, but it also gets quite close for macro shots, and focuses quickly enough to keep up with fast action. It's one of the pricier entries in Sony's catalog, but if a 135mm prime is a tool you use for portraits and other photographic disciplines, rest assured that it backs the price up with exceptional image quality.

G Master Design

The FE 135mm F1.8 GM doesn't stray from the blueprint that Sony has established for the G Master lens series. It's about average size for a lens of this type (5.0 by 3.5 inches, HD) and 2.1 pounds. It's a little smaller and lighter than the Sigma 135mm F1.8 DG HSM Art (5.6 by 3.6 inches, 2.6 pounds), which is now available in a native E-mount version.

The lens barrel is tough polycarbonate with a matte black finish. A reversible lens hood is included, as well as an 82mm lens cap and a rear protective cap. The front element features a fluorine coating, a substance that repels grease and moisture, and the lens itself is protected from dust and splashes—I had no issues using it outdoors in a snowstorm when paired with the a7R III.

There is a physical aperture ring to adjust the f-stop. It turns with satisfying clicks for precise iris control for photography, but can also be set to turn freely with the flick of a switch for continuous, silent adjustment for video recording. Two programmable buttons, which lock focus by default, are part of the design.

The lens omits optical stabilization—it's not something we're used to seeing on bright 135mm lenses, and modern Sony cameras include in-body stabilization. I was happy with the job the a7R III's in-body image stabilization (IBIS) system did to remove jitters from handheld video shot with the lens. The lack of stabilization should only be a concern if you use an older camera without IBIS.

The lens uses dual focusing groups, each driven by its own motor. The motors not only improve focus speed, but also allow for more precise adjustment. This helps to give the FE 135mm a slightly closer focusing distance than other 135mm designs. It can focus to 27.6 inches (0.7-meter) for 1:4 macro magnification. Compare this with the Sigma 135mm (1:4.3) or Zeiss Batis 2.8/135 (1:5.3).

Manual focus is available too. The large focus ring turns comfortably and with a little bit of resistance. The ring adjusts focus electronically, rather than mechanically like an SLR lens, but has a very smooth, precise mechanical feel. It's a pleasant manual focus experience.

Top-End Image Quality

The FE 135mm GM looks like other lenses from the exterior, but sets itself apart from others via its optical design. It incorporates XA elements—Extreme Anamorphic—which are molded into shapes that wouldn't be possible using traditional glass shaping and polishing techniques.

Lenses that use molded aspheric elements can show the onion ring effect in out-of-focus highlights. Instead of a smooth, defocused point of light, surface aberrations on the molded elements cause small concentric circles to appear in defocused points of light. The XA molding process is more precise, and while bokeh in our test shots wasn't completely free of the effect, it's much lesser than other lenses with aspheric elements I've used, and only really visible at a pixel level.

This goes in line with Sony's stated philosophy for G Master lens design—high resolution and smooth, beautifully defocused backgrounds. The FE 135mm blurs with aplomb at its widest apertures, and an 11-blade circular diaphragm maintains bokeh even when stopped down.

The lens does show some cat's eye effect for defocused highlights when they are placed toward the edge of the frame. This is the case with most lenses, although there are exceptions. Another Sony G Master lens, the FE 100mm F2.8 STF GM OSS, incorporates an internal apodization filter to smooth and feather defocused highlights. But it comes at the cost of brightness—the FE 100mm may be an f/2.8 lens, but it gathers light like an f/5.6 prime, so it's not the best choice for use in dim light.

We've recently had the opportunity to test the FE 135mm in the lab, so we're updating our first look with more detail. We've not been the first to do so, but our tests confirm what Roger Cicala at Lensrentals first reported: the FE 135mm is the sharpest lens he's ever tested.

See How We Test Digital Cameras

We use a different testing methodology than Lensrentals, but our tests line right up—the FE 135mm will get the most out of any sensor that you're able to pair it with today. On the 60MP a7R IV, it manages 4,600 lines when shot wide open, and peaks at an oustanding 5,333 lines when stopped down at f/5.6. With resolution this good, the numbers are academic.

Images are free of distortion, and there's only a minimal vignette visible when shooting at f/1.8. For portrait work, you may find it helpful to add a little bit of a vignette when processing photos in Lightroom or Capture One.

Premium Optics, Premium Price

With the release of the FE 135mm F1.8 GM, owners of Sony systems now have access to three lenses in classic portrait focal lengths, all included in the premium G Master series. It joins the wider FE 85mm F1.4 GM and the very specialized FE 100mm F2.8 GM STF OSS, giving photographers who prefer a tighter angle of view another tool for portraiture and other disciplines that benefit from a bright, modest telephoto lens.

Sony hopes the fast autofocus motors will make the lens a go-to option for photographers shooting indoor sports. You may typically reach for a 70-200mm zoom for activities like hockey and basketball, but in venues where lighting makes using an f/2.8 zoom difficult, the 135mm could be a substitute or supplement for a standard telezoom.

Sony has priced the lens on the high end. It debuted at $1,900, but has increased to $2,100 since. It certainly backs up its price with exceptional performance. If you think it will make a good addition to your kit, you'll not be disappointed with it in any way.

There are alternatives, of course. While the FE 135mm stands apart from the crowd with its ultra-fast autofocus (a plus for a9 and a9 II owners), you may also want to consider the Sigma 135mm F1.8, priced around $1,400, if you're just looking for a killer portrait lens.

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