315g of light weight and long focal length make a perfect partner for your photography 2 types of lenses for mirrorless and dslr camera reflex mirror lens ultra multi coating umc of samyang optics low dispersion lens ed for mirrorless samyang 300mm f63 umc cs is a compact reflex mirror lens suitable for wildlife and landscape photography and astrophotography it is available for both dslr and mirrorless cameras with aps c sensors the lens for dslr cameras