The Samyang 100mm F2.8 ED UMC is a macro telephoto manual focus lens made to fit full frame sensors. Its bright F2.8 aperture anddetachable petal-shaped hood is combined together to provide natural brightness in every photography. It features 100mm Focal Length and Circular aperture with 9 blades. High refractive and extra low dispersion lens provides the prevention of chromatic aberration and the Ultra Multi Coating technology of Samyang Optics is used to reduce flare and ghost to retain clear image. Product Features in Detail Macro Telephoto Manual Focus Lens The maximum close-up magnification is 1:1. It also can be used as 100mm telephoto lens for various purposes such as landscapes and portraits. Bright F2.8 aperture F2.8 aperture creates fantastic image with shallow depth and smooth focus gear ring allows precise adjustment. High refractive (HR) and extra low dispersion lens (ED) High refractive lens and extra low dispersion lens minimize unnecessary light dispersion and chromatic aberration effectively to produce excellent image quality. Ultra Multi Coating (UMC) technology of Samyang Optics Samyang Optics uses UMC technology to reduce flare and ghost as much as possible and get clear and fresh color image. Circular aperture with 9 blades 9 aperture blades create almost a full circle when closed and express ray beautifully as starlight.