Now the 50 f/1.2L (above right) enters the market. Being a prime Canon L Series Lens, the Canon 50 f/1.2 far exceeds all existing Canon 50mm lenses in nearly all aspects - including three negative ones: size, weight and price. Since Canon already has a 50mm f/1.4 lens, they would not release a slightly wider aperture version at a far higher price, size and weight without offering significantly better features and image quality. Otherwise, people simply would not buy the lens. The question is - are the actual differences enough?
The Canon EF 50mm f/1.2L USM Lens adds a feature lacking on the 85 L II but common on Canon's newer L series lenses - weather sealing. I should say weather-sealing-capable because a filter is required to complete the factory weather sealing. The front lens elements that extend/retract inside the lens barrel require a 72mm filter to complete their sealing. The filter attaches to the outer lens barrel - and does not rotate or extend.
If you are buying this lens, you probably intend to use it primarily at its widest apertures where it delivers best-available sharpness - and stopped down results are still very decent.
The samples on the left were sharpened with a DPP setting of 1 (very low) while the samples on the right were sharpened with a setting of 2.