Sony FE 400mm F2.8 GM OSS Lens Review: Lightest, Sharpest & Fastest Focus in Class!

Sony Finally Makes a FE 400mm 2.8 it’s a BEAUT!

Sony FE 400mm F2.8 GM OSS (Order from B&H Photo | Amazon) is the lightest, sharpest and fastest focusing four-hundred-two-eight ever made thanks to ground-breaking lens design featuring XD Linear Focus!

Previously the most obvious advantage of mirrorless camera systems were smaller camera bodies, but with this lens, the advantage shifts to advances in lens design never realized by ANY current DSLR lens.

XD Linear Focus

Sony FE 400mm F2.8 GM OSS uses XD Linear Focus actuators for the fastest AF of any super telephoto lens to date.

Why is linear focus faster than conventional rotational focus? To picture how rotational focus works, imagine unscrewing a jar lid. The distance you must turn the cap is 5X the linear distance of travel to simply pull the cap off.

Rotational helical focus worked for a century of manual focus lens design with a few notable exceptions that employed rear-group rack focus such as Canon FD 600mm f/4.5 & FD 800mm f/5.6L lenses.

DSLR AF lenses (and most mirrorless lenses) are designed using rotational focus actuators.

Sony FE 70-200mm f/2.8 GM OSS Lens bucked conventional design by pairing a linear focus actuator in the rear of the lens with a conventional rotational actuator in the front.

Sony FE 100-400mm f/4.5-5.6 GM OSS took the technology a step further by eliminating rotational focus altogether in favor of dual linear focus actuators.

Sony FE 400mm F2.8 GM OSS raises the bar with a single XD Linear Focus actuator that moves the focusing lens elements FIVE TIMES FASTER than rotational actuators used in SSM DSLR lenses. This allows the FE 400mm F2.8 GM OSS to track focus on the eyes of a moving subject at up to 20 frames per second. This simply not possible with any current DSLR lens design.

Weight

The FE 400mm F2.8 GM OSS is the world’s lightest 400 2.8 by TWO pounds! In fact it’s much closer to the weight of 300 2.8s than any other 400 2.8s.

• Sony FE 400mm F2.8 GM OSS weighs 6.38 lbs / 2895 grams
• Canon 400mm f/2.8L IS II USM weighs 8.47 lbs / 3850 grams
• AF-S Nikkor 400mm f/2.8E FL ED VR weighs 8.38 lbs / 3800 grams

Add in a camera body and Sony a9 + FE 400 2.8 GM OSS is a whopping FOUR POUNDS LIGHTER (1.812 kilograms) than a Canon 1DX II + 400mm f/2.8L IS III USM combo!

Optical Design

The FE 400mm F2.8 GM OSS features 23 Elements in 17 Groups including three Fluorite lens elements and one ED glass element to virtually eliminate both axial and lateral chromatic aberrations while maintaining corner-to-corner sharpness.

While most 400 2.8s are incredibly front-heavy, moving the AF groups to the rear – not front – of the lens allows front lens element sits five full inches of…air… Because of this, the lens balances at the focus ring – not in front of it. Coupled with the two pounds of weight it’s shed compared to the competition – it feels more like a 300 2.8 than a 400!

Construction

Magnesium alloy construction provides durability to hold up to heavy use yet it’s light weight helps trim two pounds from the weight of competing lenses.

Sharpnness

Canon 400mm f/2.8L IS III USM and AF-S Nikkor 400mm f/2.8E FL ED VR are excellent lenses – among the best lenses Canon & Nikon ever made. But they simply don’t match the corner-to-corner sharpness of Sony’s FE 400mm F2.8 GM OSS:

(Click to View Larger)

Teleconverters Add Versatility

The FE 400mm F2.8 GM OSS pairs perfectly with the Sony FE 1.4X & FE 2X Teleconverters offering the added versatility of a 560mm F4 and 800mm F5.6

Sony FE 1.4X & FE 2X Teleconverters perfectly pair with FE 400mm F2.8 GM OSS

Lens Features

Sony FE 400mm F2.8 GM OSS Lens Control Panel on the left side

Sony FE 400mm F2.8 GM OSS Lens Foot features one 3/8″-16 and two 1/4″-20 threads

The Lens Includes a Drop-In Filter Holder that accepts 40.5mm ND and other filter types, as well as the optional VF-DCPL1 Drop-in Circular Polarizing Filter. The VF-DCPL1 filter can be rotated to achieve desired polarization while installed in the lens.

The fitted foam filled case includes cut-outs for FE 1.4X & 2X teleconverters

Price and Availability

Best-in-class doesn’t come cheap. Sony FE 400mm F2.8 GM OSS is available for pre-order for $11,998 from B&H Photo | Amazon). The first lenses are expected to arrive in the USA in September 2018.

Testing Notes

Testing was done using Sony a9 with Beta Firmware 2.10 which adds full 20 FPS AF support for the Sony FE 400mm F2.8 GM OSS Lens. (Sony a9 fw update 3.00 will be released today.)

Sony a9 firmware 3.00 adds a couple new settings:

Menu > Camera Settings 2 > Custom Operation 2 > Function Ring (Lens) > Power Focus / APS-C S35 /Full Frame Select
Power Focus allows smooth focus pulls for video. Still shooters should ignore this setting an instead choose APS-C S35 /Full Frame Select which allows you to toggle between Fullframe and APS-C Crops by rotating the Function Ring just below the focus hold button.

Sony FE 400mm F2.8 GM OSS Lens Function Ring is just below the focus hold buttons.

Menu > Setup 7 > Write Serial Number > On
Turning this setting on will write the camera serial number into the EXIF which is very handy if you own more than one of the same camera bodies and one is acting up.