Samyang/Rokinon has announced a new ultra-compact, ultra-wide-angle prime for Sony full-frame mirrorless cameras. At just 145g light, 2-inches long, and $500, the new Samyang AF 18mm f/2.8 lens is “the most compact, lightweight, and affordable super-wide angle full frame lens for Sony E mount.” Despite its diminutive size, the Samyang/Rokinon AF 18mm f/2.8 offers a rectilinear 100.1° angle of view when used on Sony’s full-frame mirrorless cameras. Attach it to the new Sony a6600, and the lens crops to a…