Abbreviation used by Sigma to mark Optical Stabilizer Function in their lenses. Usually contained in lens name eg. (18-50mm F2.8-4.5 DC OS HSM) Translated to Canon terminology it equals to IS (Image Stabilizer)
Source:Special portrait lens that allows for taking softened photos without additional filters thanks to its special optical design.
Posted by: Sergei Borodin 23.05.2012 16:31:38Lens with a viewing angle of 180 degrees diagonally or horizontally without distortion correction.
Posted by: Sergei Borodin 23.05.2012 16:29:38