Full-Frame E-mount. As a part of the FE line of lenses, the FE 600mm f/4 GM is designed to cover the full-frame sensors on Sony E-mount cameras. Since it’s an E-mount lens, it’s also fully compatible with APS-C NEX cameras.

Versatile Super-Telephoto Prime. When used on a full-frame camera, the FE 600mm is an ideal choice for sports, news, wildlife, and nature photography. Using an APS-C sensor camera? You’ll have a focal length equivalent to 900mm. The constant f/4 aperture is plenty fast for shooting in decent light, but may prove to be a tad slow for low-light shooting.

Extreme Dynamic Autofocus System. This lens’s Dual Linear Motor autofocus system provides fast, silent autofocus performance with physical focus hold and limiter options for fine tuning. When Full-Time Direct Manual Focus is engaged, you can instantly switch from autofocus to manual-focus mode by simply rotating the focus ring.

Optical Image Stabilization. The in-lens stabilizer allows you to shoot at lower shutter speeds without having to worry about camera shake. You can choose between three image-stabilization options: Mode 1, which is suited to most types of shooting; Mode 2, which is specifically intended for use with panning movements; and Mode 3, which provides a more stable viewfinder image for easier framing of action shots.

Advanced Optics. The FE 600mm’s 18-group/24-element design includes two extra-low dispersion elements, three fluorite elements, and one XA element for minimizing chromatic aberrations and distortion, and for producing high-clarity images. The rounded eleven-blade aperture diaphragm produces smooth out-of-focus highlights, and the Nano AR and fluorine coatings keep flare and ghosting at bay.

G-Master Series Quality. The GM series is Sony’s premium lens offering. What sets it apart from other Sony lenses is an emphasis on an extremely high resolving power of fifty lines per mm, out-of-focus “bokeh” quality, and a robust, weather-sealed body.

Teleconverter Compatible. This lens is compatible with Sony’s 1.4x and 2.0x teleconverters, which will give you up to a 1200mm focal length, or up to an 1800mm focal length on APS-C cameras. Teleconverter use doesn’t compromise the lens’s G Master image quality or its autofocus performance. You get an f/5.6 maximum aperture with the 1.4x teleconverter and an f/8 maximum aperture with the 2.0 teleconverter.