Sony FE 100-400mm F/4.5-5.6 GM OSS

This Sony telephoto zoom covers 100–400mm on full-frame Sony E bodies. That reach suits wildlife, outdoor sport and other distant subjects you cannot approach. Airshows and distant landscape detail also fit the range. The zoom lets you widen to 100mm when an animal moves closer, then tighten to 400mm for a tight frame.

Sony introduced the lens in 2017. The main trade-offs are weight and light gathering. The maximum aperture narrows as you zoom, so bright conditions help when fast action needs a high shutter speed.

The lens weighs 3 lb 1.2 oz (1395 g) without its tripod mount and measures 8.07 in (205 mm) long and 3.7 in (93.9 mm) across. Consider a monopod or rest during long sessions. A screw-in filter must match the 77mm thread to attach directly.

At 400mm, a distant animal or player appears larger than at 100mm from the same position. The short end includes more surroundings and helps when action moves closer. A narrow view can make a fast-moving bird hard to find, so start at a shorter setting when needed.

The maximum aperture changes from f/4.5 at 100mm to f/5.6 at 400mm. Under grey skies or toward dusk, you may need a higher ISO to keep a fast shutter speed. A still subject gives more freedom to slow the shutter when the camera is steady.

Closest focus is 3.2 ft (98 cm), measured from the sensor. Maximum magnification reaches 0.35x, useful for flowers and larger details. Leave space ahead of the glass and avoid shading a nearby object. Very small subjects will still occupy a modest part of the frame.

At long settings, a nearby subject can have a soft background even at f/5.6. More space behind the subject makes that separation easier. Branches directly behind an animal can remain distracting, so change viewpoint when possible.

Built-in stabilization reduces camera shake and steadies the view at long focal lengths. It helps with still subjects at slower shutter speeds. Firm support remains useful during long waits. A sprinting player or moving animal still needs enough shutter speed for its movement.

Dust and moisture resistance help outdoors. Use cover in persistent rain. Fluorine coating helps water and oily marks wipe away from the front glass. Remove loose grit before wiping spots or fingerprints.

A smoothness adjuster changes how much resistance you feel when turning the zoom ring. Lower resistance allows quicker adjustments; more resistance gives a firmer feel. It is not a switch that locks the lens at a chosen focal length.

The design uses 22 elements in 16 groups. Two ED elements and one Super ED element help reduce chromatic aberration, the coloured fringes that can appear along high-contrast edges. A bird against bright sky is one place those fringes can show. Floating focus changes the relative positions of focusing groups for close work.