South & Southeast Asia
South & Southeast Asia
Optical image correction by the lens covers chromatic aberration correction, distortion correction, and image stabilization. Distortion is corrected by elements in the first group. This made it much more challenging to produce the molding glass-molded aspherical elements in this group.
Development and production teams work across the street from each other at the Utsunomiya plant, and after volume production began, I often went across the street to the factory. Maintaining consistent image quality throughout the zoom range is always difficult, so in design, we must strike the right balance of performance. For this lens, performance is balanced to provide more consistent image quality in the distance on the wide-angle end than EF16-35mm f/2.8L III USM, because wide-angle lenses are often used to shoot far-off landscapes, focusing at infinity and at a wide angle. And because the aperture is often stopped down for landscapes, this optical design also ensures superior image quality under these conditions.
Besides incorporating glass-molded aspherical elements and UD elements, each lens group is designed to have a high refractive power, for bending light, which makes production very challenging. This is especially true for the first and fifth lens groups, and optical performance is constantly monitored.
Canon lens manufacturing spans more than 75 years, and production volume has topped 160 million lenses. Over the course of lens development and production, we have conducted R&D on digitalization for consistent quality and precision, coating technologies to suppress ghosting and other issues, and assembly techniques enabling advanced optical adjustment, which we apply in production. As I’ve said, production is also very challenging for this product, and we struggled with it initially. But without a doubt, the technical insight gained from it can be applied to enhance image quality in current and future RF lenses.