The 2x EX is placed in the same way and it allows the photographer to use the 70-200mm f/2.8 lens as a 140-400mm f/5.6 telephoto zoom lens, and the 300mm f/2.8 lens as a 600mm f/5.6 ultra telephoto lens.
|Lens construction||6 elements in 5 groups|
|Focal length||2x that of a master lens|
|Aperture coupling range||F2.8 - F32|
|Reproduction ratio||2x that of a master lens|
|Dimensions||68.5 X 52mm
(2.7in. X 2.0in.)
*Dimensions and weight include the SIGMA mount.