EF 400mm f/2.8L IS III and EF 600mm f/4L IS III developers talk

Canon USA has published an interview with the developers of the brand new EF 400mm f/2.8L IS III and EF 600mm f/4L IS III super telephoto lenses.

The EF 400mm f/2.8L IS III USM and EF 600mm f/4L IS III USM take their places as the world’s lightest professional super telephoto lenses in their class. The weight of the EF 400mm f/2.8L IS III USM and EF 600mm f/4L IS III USM lenses has been reduced by 2.2 lbs. (more than 25 percent) and 1.9 lbs. (more than 20 percent) respectively.

EF 400mm f/2.8L IS III costs $11,999 while the EF 600mm f/4L IS III USM priced at $12,999.

Some of the design goals and challenges facing the developers:

Rather than simply making the lens lighter, we retooled the lens from the ground up for an overall balanced weight.
Improved mobility and portability, with reduced weight
A significant — not average — reduction in weight
We were convinced we could reach our goal thanks to the
proposal of a new optical system.
New challenges, one after the other, with tag-team efforts
between Optical Design, Mechanical Design, Electrical
Design, and Production that overcame these challenges.
Reducing the number of component s results in both
a lightweight design and increased strength.
Using a new high-strength alloy for the lens barrel
Using the latest gyro sensor is insufficient for improved
IS performance — it was necessary to build a new control algorithm that assumes a variety of situations.
Not only has handheld IS performance improved, but it can
now deal with vibration when using a tripod.
Improved lens focus drive speed even when an EF tele-extender is attached.
An expert coating team was formed with the cooperation of the
Mechanical and Manufacturing departments within Canon, to aim
for an ideal solution.
We didn’t compromise on the white color, despite placing
priority on functionality.