Exclusive: Zeiss Refutes Rumors Cosina Developed Otus ML Lenses

Despite rumors to the contrary, Zeiss tells PetaPixel that it did develop its new series of Otus ML prime lenses for full-frame mirrorless cameras.

Last week, Japanese photography blog Asobinet published a Japanese patent application filed by Cosina that appeared to show the optical design for the Zeiss Otus ML 85mm f/1.4 lens released last year.

English-language media followed up earlier this week, speculating that Cosina may have designed Zeiss’ new Otus ML lenses, which themselves reflect Zeiss’ serious recommitment to the photography space after a relatively lengthy quiet period.

It is not unusual in the photography space for multiple companies to work together on a lens. For example, a significant portion of Tamron’s photographic optics business includes making lenses for other companies, most notably, Nikon.

However, as Zeiss tells PetaPixel, any claims that Cosina, a respected Japanese lens maker best known these days for its Voigtländer-branded lenses, developed the Otus ML primes are false.

“There have been recent rumors suggesting that the ZEISS Otus ML lenses were developed by Cosina. These claims are incorrect,” Joachim Kuss, Head of Communications, Zeiss Consumer Markets Segment, tells PetaPixel.

“The optical design and mechanical concept of the ZEISS Otus ML family is the result of ZEISS’ own development, building on decades of our lens design expertise and the heritage of our renowned Otus lenses. ZEISS is and remains fully responsible for the concept, specification, and design of these products.

“As is common practice in the optical industry, ZEISS collaborates with selected manufacturing partners for production. Such collaborations, however, do not change the fact that the underlying design, performance targets, and quality standards of ZEISS lenses are defined and owned by ZEISS.”

While this response to PetaPixel‘s inquiry and Cosina’s Japanese patent application do not shut the door on the notion that Cosina is one of Zeiss’ “selected manufacturing partners,” it does squash rumors that Cosina designed Zeiss’ new Otus ML lenses, rather than the legendary German optics company.

It sounds like Zeiss is responsible for the concept, development, and design of the optical and mechanical aspects of the three Otus ML lenses, and presumably for any future Otus ML lenses potentially in the works. Any outside party is strictly involved in manufacturing.

Photographers can debate at what point a lens stops being one company’s creation and starts being another’s, but to characterize the new Zeiss Otus ML lenses as being anything other than Zeiss lenses would seem a bridge too far.

As Zeiss explained to PetaPixel at CP+ 2025, immediately after the company unveiled its first two Otus ML lenses, the 50mm f/1.4 and 85mm f/1.4, it took the design and development of the manual-focus primes very seriously.

“We had to bring this same experience and same magical images to a compact and lightweight form,” said Petra Visuri, Product Manager of Photography and Mobile Imaging, Zeiss Photonics and Optics (PNO). Visuri noted that the Otus ML lenses were spiritually very similar to the company’s legendary Otus lenses for DSLR cameras.

“For us, you have a photograph, you have a certain vision in mind of what you want to capture. We want to enable you to capture that in the way you saw it with the colors as they are in real life, the sharpness, and so on,” Zeiss explained last year.

“We have this long history, and all that history informed the Otus ML. We all know the market has changed, and we took time to understand how we can help photographers differentiate themselves from the mass of taps on the display or clicks on the camera — create unique images. That took time, and now we have the Otus ML,” Visuri concluded.

Zeiss is adamant that it is the company responsible for the Otus ML lenses. The concept, development, and design are Zeiss’ work. Zeiss takes complete credit for its new Otus ML primes, even if another company is involved with production.

Image credits: Zeiss