Abbreviation: DC = "DC for Digital" (Sigma)

The abbreviation DC means "DC for Digital" and is seen on Sigma products.

Explanation from Sigma

These are special lenses designed so that the image circle matches the smaller size of the image sensor of most digital SLR cameras. Their specialized design gives these lenses the ideal properties for digital cameras, the compact and lightweight construction is an added bonus ! including compact and lightweight construction.

These are dedicated digital SLR camera lenses with an image circle designed to suit image sensors that correspond to APS-C size. Inhouse technology accumulated through the development of our digital SLR camera was used to optimize optical performance for our digital lenses. This is a high-performance lens series that fuses technology such as lens power layout and coating design with the know-how Sigma has built up over many years of developing interchangeable lenses for SLR cameras. By reducing the diameter of the image circle, Sigma has achieved a more compact, lightweight lens series.

See examples of effected products

	Sigma EX 50-150mm F2.8 DC APO HSM
	Sigma 8-16mm F4.5-5.6 DC HSM
	Sigma 17-70mm F2.8-4 DC HSM OS Macro

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