The Sigma 180mm f/3.5 EX DG APO Macro IF HSM lens is a high performance telemacro lens that can focus from infinity to full 1:1 lifesize reproduction without accessories.
Convenient for photographing subjects, which are not easily approached, the 180mm f/3.5 Macro features apochromatic design, two SLD (Special Low Dispersion) glass elements, and a floating inner focus (FIF) system. A focus limiter switch aids in faster AF by restricting the movement of the focusing mechanism to a smaller portion of its enormous range. Usable with Sigma's 1.4X EX teleconverter as a 252mm f/4.9 lens providing AF function from infinity to about 47" or with the 2X EX teleconverter as a 360mm f/7 lens in manual focus.
This lens is designed as a high-quality macro lens, good for film or digital SLR cameras. The improved DG lens design corrects for various aberrations. This macro lens is specially coated to get the best color balance whilst cutting down on ghosting caused by reflections from the digital image sensor. The lens provides the utmost correction against lateral chromatic aberration, which is a serious problem for digital SLR cameras.