The Sigma 18-50mm F/2.8 DC EX Macro is designed to suit the characteristics of DSLR cameras, this lens delivers an extremely high level of optical performance. The Sigms 18-50mm is a relatively quiet, compact, and lightweight zoom lens. This lens has minimum focus distance of 0.2m and employs a .2x magnification factor. The internal focusing does not change the length during focusing, thus eliminating front lens rotation. SLD glass elements help eliminate chromatic aberrations while providing superb image quality throughout the zoom range. Super Multi Coating on the glass minimizes flare and ghosting and ensures high contrast images. The EX lens series signifies excellence of engineering and new technology.