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

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. 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.