canonin sigmat

DG = täysikennolliseen
DC = APS-C kennolliseen

DG (DG for Digital)
These are large-aperture lenses with wide angles and short minimum focusing distances. With an abundance of peripheral illumination, they are ideal lenses for Digital SLR Cameras whilst retaining suitability for traditional 35mm SLRs.

DC (DC for Digital)
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.

http://www.sigmaphoto.com/sigma-lens-technology