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Behind the curtain – The Cooke Factory

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By: The Cooke Team  |   2 min read

The Cooke factory, located in Leicester UK, possesses a unique ambiance which seamlessly blends contemporary techniques with age-old traditions and machinery. Fuelled by a team driven by passion, their unwavering commitment empowers Cooke to craft enduring products known for their exceptional quality and lasting for decades.

“Something is well designed when it’s practical and reliable but also elegant.”

Graham Cassely, Optical Designer – Cooke Optics

 This ethos has been imbued in Cooke from the beginning and some of the machines in the factory date from the start of the company also. Whilst advances in machining have been embraced and utilised by Cooke, there is fantastic value to be had in combining new and old technological processes – in some cases the older processes give more favourable results. Throughout the extensive manufacturing process there is a handcrafted, human element.

“I really like this idea of making all the glass elements in a very persistent way. We’ve got more control to how the glass is going to behave.”

Kate Figurska, Mechanical Design Engineer – Cooke Optics

The factory is spread over two floors. The ground floor operates as a gigantic clean room with people working in coveralls carrying out clean work which includes coating, cementing and final assembly. Upstairs the “dirty” work is carried out – metal work, iris build, outer assemblies and the like. Throughout the process these two spaces work in tandem with one another.

The “outer” of a Cooke lens is the metal work that you interact with: the outer barrel, the focus and iris gear and lens mount. The “inner” of the lens is where all the glass is. Cooke build the outer and the inner separately, and then when they are ready, the inner slides into the outer and it’s all locked together.


“We use a lot of new technology here which is great for consistency and repeatability. The ethos of the Cook factory is that we don’t just want to make lenses with great imaging, we want to make lenses that are built to last as well.”

Graham Cassely | Optical Designer – Cooke Optics

 The glass side of the process unfolds through a series of meticulous steps. Firstly, glass arrives from one of two suppliers, either based in Germany or Japan. Initially rough and untreated, the glass is larger than its refined and shaped form.

Pre-edging, grinding, and polishing are meticulously executed, utilizing state-of-the-art CNC machines alongside traditional equipment, each excelling in specific tasks. Master polishers work within exacting tolerances. Once the first surface is polished this side will be painted black for protection whilst the second surface is polished before also being sprayed.

Upon entering the coating clean room environment the black paint is removed, revealing the perfect surfaces ready to be coated. The precise chemical makeup of these coatings is closely guarded insider information!

Edging involves mounting a lens element onto a chuck with heated tar (pitch), ensuring alignment with the optical centre. Machines then precisely edge the lenses to their required dimensions. The heated pitch means the lens can be easily removed from the chuck without leaving marks. Once removed, the edges of any lens elements that could reflect or scatter light into the image are painted black.


Complete lens assembly involves meticulous integration of all elements to form the lens inner, followed by a thorough alignment check. If successful, the assembly is disassembled, cleaned for a final time, and reassembled in a clean room environment. Typically, a single technician oversees the entire part of this process for each lens, ensuring precision and consistency. Then the inner is fitted to the corresponding outer. Lenses are made to order to maintain uniformity across sets.

“Those details, what we are making sharp on an image, what we are trying to blur, it’s very important how the lens is being used to capture emotions.  As we consider perfect design there is never an end point, there will be always an improvement, there will be always something else. It’s a never-ending journey.”

Kate Figurska, Mechanical Design Engineer – Cooke Optics

Beyond manufacturing the factory also functions as a service centre and training space for rental company technicians. General servicing can include glass cleaning, a check over the lens mechanics and re-greasing but more extensive tasks such as cam replacement are also common.

“The ethos of the Cooke factory is that we don’t just want to make lenses with great imaging, we want to make lenses that are built to last as well. People are still using Speed Panchros that were built 70 or 80 years ago and I like to think that people will still be using lenses that we’re building now in another 70 or 80 years.”

Graham Cassely, Optical Designer – Cooke Optics

Creating Cooke Lenses

Directed by Dino Kazamia
Cinematography by Dylan Bruce