The kind of quality for which Sigma is pertpetually striving can be summed up by two adjectives: ”essential” and ”optimal”. Now that digital images are everywhere, lens performance requirements have become dramatically higher and more stringent. Photos can be displayed on computer screens and examined at the pixel level, so lens aberrations show up clearly, and differences in lens performance are obvious at a glance. This is precisely why we are focusing on genuinely high picture-quality, doing our utmost to eliminate lens aberrations at the manufacturing stage, and determinedly striving to ensure that optical data reaches the image sensor with no interference on the way.