Compared with their predecessors, the EF500mm is 680g/24oz. lighter resulting in a significant weight reduction. Higher level of image quality has been achieved by the new optics which features two fluorite lens.
The Image stabilizer’s shutter speed equivalent has been increased from around two times faster to approximately four times faster. The ISMode 2 has been improved and the lenses have been equipped with an all new ISMode 3 which only activate the IS mechanism when during shutter press.
Improved durability and toughness resulting from an overall part redesign by the optimal positioning of each type of switch and other elements in the lens control area to achieve optimal weight balance.