Sigma 28mm F1.8 EX DG Aspherical Macro Wide Angle Lens

The lens has an advanced optical construction, in order to obtain adequate peripheral brightness with open aperture. Also, the iris diaphragm has 9 diaphragm blades to obtain beautiful out of focus images in the foreground and background. The lens incorporates a Dual-Focus (DF) mechanism. It is easy to hold the lens, since the focusing ring does not rotate during auto-focus, yet it provides adequate focusing torque of the focusing ring during manual focusing of the lens. Also, this also allows the use of a Petal-type Hood and the easy use of a polarizing filter.