Samyang 12mm f/2.0 NCS CS is a perfect ultra wide angle lens for APS-C mirrorless cameras with Cropped Sensors (CS). it is a high performing lens, especially suited to cameras fitted with a high resolution sensor (above 24MP). Samyang lenses offer great quality optics at affordable price, the new Samyang 12 mm is expected to be one of the best wide-angle prime lenses available in its class. The Samyang 12 mm offers an equivalent wide angle of 18mm on APS-C sized sensors, 24mm on Micro Four Thirds (MFT) mount. A fast aperture of f/2.0 allows shooting even in lower light conditions. Optical construction of the lens comprises 12 elements divided into 10 groups including one aspherical lens (ASP) and one hybrid aspherical lens (H-ASP). There are also three lenses made of ED glass, offering superb performance. Technologically the Samyang 12mm lens is the most advanced Samyang lens to date. This lens is in good overall condition with some signs of use. The glass is clean and in good condition. The lens barrel shows some cosmetic marks. There is some light dust within the lens, which would not affect optical performance at all. The focus ring is in good condition. The lens mount shows signs of use.This lens has moisture within the internal elements.