YouTube channel Process X creates videos showing how a diverse range of products are made, and a new video takes viewers to Sigma’s factory to show how a lens is manufactured.
The nearly 25-minute video, first seen on Fuji Rumors, shows Sigma’s lens production process from start to finish, including creating and shaping individual glass elements, building lens barrels and actuators, and putting everything together into a finished product.
Cutting and polishing individual glass lens elements is among the earliest step in making photographic lenses. Modern lenses are extremely sophisticated and the ultimate in image quality performance depends on each element in an optical formula being precisely cut, shaped, and polished. Every individual component works with the rest of the optical design, so it is vital that each element meets Sigma’s strict specifications.
After cutting and shaping the lens elements, some require special coating and further treatment to ensure optimal performance. Beyond sophisticated coatings like Sigma’s Super Multi-Layer Coating to reduce flare and ghosting, the edges of some elements are treated with special black ink.
However, as the video shows, making a lens goes far beyond the glass itself. Modern autofocus lenses feature complex motors, including Sigma’s Hyper Sonic Motor (HSM) autofocus system. They also have gears and cams to precisely control autofocus groups and zoom rings, which are sometimes marked by hand. Enabling these components to coordinate with a wide array of cameras also requires a lot of electrical components.
Further, assembling all of these pieces of glass, metal, plastic, chips, and wires must be done in such a way as to ensure that no dust gets into the lens during construction and that the photographer will be able to reliably use the lens in adverse weather conditions. Many of Sigma’s lenses have robust weather sealing, which adds a layer of complication to the production process.
While the full video above is quite lengthy, it is a fascinating look at modern lens production and helps show how much work and effort goes into making even a single photographic lens. It is interesting to compare Process X’s new video to a Sigma factory video tour by CineD in 2018.
PetaPixel has featured many similar factory tours over the years, including a recent one published by Fujifilm and a brilliant look at Kodak film production created by the YouTube channel Smarter Every Day.
Image credits: Featured image by Process X