Breakthrough technology developed by Marumi makes DHG Achromat filters ideal for macro photography. Achromat Macro Filters are designed to shorten the focal length of your lens and enhance its macro mode capabilities with outstanding clarity. Other filters can provide simple magnification but only Marumi Digital High Grade DHG Achromat Macro filters provide the edge-to-edge sharpness detail and clarity that professionals demand.nbspnbspThese Achromat Macro lenses employ two lens elements of a special crown glass that is highly durable and features a low refractive index and low dispersion having similar properties that are laminated together. The two laminated elements are with ultra-low-reflection coating for improved light transmission. To minimize internal reflection DHG filters feature an outer satin-smooth rim with an ultra-thin matte black filter frame.