Lens Construction 13 Elements in 11 Groups Angle of View 94.5 degrees Number of Diaphragm Blades 9 Blades Minimum Aperture F22 Minimum Focusing Distance 20cm/7.9 in. Maximum Magnification 1:4 Filter Size Diameter 82mm Dimensions Diameter 88.6mm X Length 89.5mm 3.5 in. X 3.5 in. Weight 520g/18.3 oz. Corresponding AF Mounts SIGMA,