This large aperture telephoto lens completely compensates for aberrations by adopting an aspherical lens optical system and offers high-contrast definition without flare even at maximum aperture. When it was released, this was the brightest SLR 85mm lens with an aperture of f/1.2.
Normally, aspherical lenses require advanced design technology and extremely high-precision production technology, making them special lenses with a high price tag. However, Canon has fully utilized the latest technology such as measuring machine using laser light, grinding stones using special materials and electronics technology for controlling polishing machines. By doing so, we have established mass production technology with a precision better than 0.1 microns (1/10,000 of a millimeter) that was considered difficult to achieve even in the laboratory, and this has made it possible to mass produce like normal lenses and provide products to the market at a reasonable price.
This was the first 85mm telephoto lens to incorporate a compensation mechanism (floating system) for preventing deterioration of images due to aberration changes in close shooting, while offering high performance at all distances from maximum to a small aperture through appropriate power distribution using advanced design technology and the selection of the appropriate glass material.
The lens also exhibits Canon’s own high level of technology such as optimal color balance obtained through super spectra coating of multiple layers.