Developer Interviews on the Canon 85mm 1.4L IS USM
Canon Asia has posted an article with developer interviews on the 85mm 1.4 L IS USM.
The 85mm 1.4L IS USM has had excellent reviews since it's release this year and at a glance;
l Aperture Range: f/1.4 to f/22
l One GMo Aspherical Element
l Air Sphere and Fluorine Coatings
l Ring-Type Ultrasonic Motor AF System
l Optical Image Stabilization
l Dust- and Water-Resistant Construction
l Rounded 9-Blade Diaphragm
A quote from the article part 1 and part 2 of the article, which is certainly worth the read.
Iwamoto: In 2006, Canon released the EF85mm f/1.2L II USM as its flagship lens in the 85mm focal range, and the lens has gained an outstanding reputation for its smooth, creamy bokeh quality. The optical design of the EF85mm f/1.4L IS USM, on the other hand, leans more towards providing sharp and crisp delineation, while maintaining the rich expression of its f/1.2 counterpart. We also took into consideration how users would probably most often compose their portraits to place the subject in the centre of the frame, and therefore struck a balance, where the resolution at the centre of the image is capable of providing clarity befitting an L lens, while at the same time, you also get beautiful bokeh quality at the image peripheries.
We proceeded with development to achieve such resolution while taking realistic weight, size and cost into consideration.