Sony has a new super-telephoto zoom for full-frame E-mount. The FE 100-400mm F5.6-8 OSS pairs a long reach with Optical SteadyShot stabilization in a body far smaller than the focal range suggests.
Compact design
At 6.5 inches (164.5mm) long and 3.1 inches (78.2mm) in diameter, the lens stays manageable. It does extend as you zoom, so that’s the retracted figure. Weight lands at 1.4 pounds (654g), which is remarkably light for the category. Onboard controls cover a customizable focus hold button, a focus mode and range switch, plus a zoom lock.
Optical construction
Fifteen elements sit in 10 groups, including two ED glass elements and two aspherical elements. Sony credits that arrangement with holding down chromatic and other aberrations.
Optical SteadyShot handles stabilization with a physical on/off switch on the barrel. The lens also works with a camera body’s Active Mode stabilization and supports coordinated stabilization on compatible bodies.
Autofocus
A linear motor drives focus, which Sony describes as fast, precise and quiet. On the α9 III, the lens keeps up with continuous shooting at roughly 120 frames per second with AF and AE tracking.
Minimum focus distance runs 3.71 feet (1.13 meters) at 100mm and tightens to 2.83 feet (0.86 meters) at 400mm. Maximum magnification hits 0.41x. That’s not macro territory, but it’s close enough to fill a frame with a small subject.
Aperture
The maximum aperture starts at F5.6 and drops to F8 by 400mm. That’s the cost of the size. A constant-aperture 400mm would be several times the weight and price. Long focal lengths still produce shallow depth of field even at F8, and the 9-bladed circular diaphragm should keep out-of-focus highlights round.
The variable aperture is a real problem for video, though. Zooming during a shot shifts exposure, so you either lock the focal length or ride the settings mid-take.
Other features
A dedicated lens hood ships in the box to cut flare. The dust and moisture resistant build means bad weather isn’t automatically a wrap. Sony’s optional teleconverters push the maximum reach to 800mm, or an equivalent 1200mm on an APS-C body.
What we think
Plenty of shooters will write this lens off over the aperture. That reaction misreads what it’s for.
A 400mm at 1.4 pounds is a lens you actually carry. The fast constant-aperture alternatives sit in a bag at home more often than their owners admit, because a 6-pound lens changes what a hike looks like. For wildlife and outdoor sports, both shot in daylight anyway, F8 at the long end is rarely the limiting factor. Available light usually isn’t the constraint. Willingness to haul the thing is.
The variable aperture is the honest strike against it for video work. Anyone who zooms during a take will fight it, and no amount of stabilization fixes that. Lock the focal length and it disappears as a problem.
At $850, this is the cheapest way into serious reach on E-mount. Low-light work needs a different lens. Daylight work at distance doesn’t.
Pricing and availability
The Sony FE 100-400mm F5.6-8 OSS ships in September at $850.
