Focal length and maximum aperture 85 mm f12 lens construction 8 elements in 7 groups diagonal angle of view 28deg 30deg focus adjustment front group linear extension usm closest focusing distance 095m 31ft filter size 72mm with a large maximum aperture of f12 this is the fastest 85mm telephoto lens in its class with a large maximum aperture of f12 this is the fastest 85mm telephoto lens in its class one aspherical lens element and two high refractio