Sigma 180mm F3.5 EX DG lens
Encyclopedia
The Sigma APO 180mm F3.5 EX DG lens is a telephoto
Telephoto lens
In photography and cinematography, a telephoto lens is a specific type of a long-focus lens in which the physical length of the lens is shorter than the focal length. This is achieved by incorporating a special lens group known as a telephoto group that extends the light path to create a long-focus...

/macro lens produced by Sigma Corporation
Sigma Corporation
is a Japanese company founded in 1961, manufacturing cameras, lenses, flashes and other photographic accessories. All Sigma products are produced in the company's own Aizu factory in Bandai, Fukushima, Japan...

. It contains two SLD (Special Low Dispersion) glass elements to provide correction for chromatic aberration. It is aimed toward advanced consumer
Consumer
Consumer is a broad label for any individuals or households that use goods generated within the economy. The concept of a consumer occurs in different contexts, so that the usage and significance of the term may vary.-Economics and marketing:...

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