The ROKINON AF 18mm F2.8 Full Frame Lens for Sony E mount is optimized for portability, compactness, and ergonomic handling. It is ROKINON‘s fourth compact lens designed specifically for Sony mirrorless cameras which are surprisingly capable for their size. At 5.12oz in weight and 1.99” in length, it is the most compact, lightweight, and affordable super-wide angle full frame lens for Sony E mount. The 18mm focal length provides a rectilinear 100.1° super wide angle view that is especially suitable for landscape, interior, architectural, and night sky applications. For Sony APS-C sensor cameras, the focal length is equivalent to 27mm with a 76.2° field of view. Optically, the lens is made up of nine Ultra Multi-Coated elements in eight groups. Eight specialized lens elements (3 Aspherical, 2 High Refractive Index, and 3 Extra-low Dispersion elements) combine to minimize distortion and ensure high image sharpness, clarity, and contrast. The internal focusing design of the ROKINON AF 18mm utilizes a STM (Stepless Motor) for quiet, smooth and precise autofocusing to 9.8”. This also prevents both changes in length and front element rotation to enable easy use of 58mm polarizing and other filters that require precise positioning. This compact wide-angle optic is designed with a metal mount and glass strengthened composite material to reduce weight while increasing durability. Each lens comes equipped with a removable petal-shaped hood, lens caps, and a custom fitted case.