Full-Frame E-mount. As a part of the FE line of lenses, the Sony FE 135mm f/1.8 GM is designed to cover the full-frame sensors on Sony a7- and a9-series cameras. Since it’s an E-mount lens, it’s also fully compatible with APS-C cameras as well. On an APS-C camera, you’ll get a focal length equivalent to 202.5mm

Pro-Grade Medium Telephoto Prime. The FE 135 GM’s fast f/1.8 aperture and medium tele focal length make it perfect for portrait photography. At f/1.8, you’ll get dramatic, shallow depth of field and excellent performance in low light.

XD Linear Motor Autofocus System. This internal focusing system provides fast, nearly silent, and highly accurate performance that’s great for still and video use. Two dedicated focus hold buttons and an AF/MF switch help to tailor focusing to your shooting needs. There’s also a manual aperture ring that can be “de-clicked” for smooth aperture adjustment when shooting video.

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.

Advanced Optics. The FE 135 GM uses one “XA” extreme aspherical element, one extra-low dispersion element, and one Super ED element to minimize spherical and chromatic aberrations, and to produce incredibly sharp, high-contrast images. The rounded eleven-blade aperture diaphragm produces smooth out-of-focus highlights when you desire a shallow depth of field.