Ref.: https://myfunleader.com/
PRESS RELEASE
The Story Behind the Contax G to Leica M Conversion Project
The project aims to bring classic Contax G lenses, originally designed for the Contax G autofocus rangefinder system of the 1990s, to modern Leica M cameras without permanently modifying the original lenses.
A Classic System
The Contax G system, developed by Contax and Carl Zeiss, debuted in the mid-1990s and included several well-known lenses such as the Planar 35mm f/2, Planar 45mm f/2, and Biogon 28mm f/2.8. While the cameras themselves have long been discontinued, the lenses remain popular among photographers for their distinctive rendering and strong optical performance. Many photographers who own these lenses also use Leica M cameras, which has led to ongoing interest in adapting the lenses to the Leica M mount.
A Non-Destructive Approach
Rather than permanently altering the optics or original mount, the conversion kits are designed to be installed without modifying the lens itself. The optical elements and original Contax G mount remain intact.
Development Timeline
The project began in 2019 with the release of the G35 conversion kit, which adapted the Planar 35mm f/ 2 for Leica M cameras. While the first version proved popular and sold out quickly, the team continued refining the design. In 2021, the G45 conversion was introduced for the Planar 45mm f/2. Improvements included smoother focus damping and refinements to the internal mechanical structure. These updates later informed the release of G35 v2.0 in 2025, which featured a redesigned focusing mechanism and improved internal construction based on user feedback. The series now concludes with the G28 conversion, announced in 2026.
Materials and Design
For the G28 project, the team selected a combination of materials to balance durability and weight. The internal structure uses brass components for stability and longevity, while the outer housing is made from aluminum to keep the overall weight manageable.
Three Lenses for Everyday Photography
Together, the three converted lenses cover a practical focal range:
• G28 – 28mm f/2.8 Biogon (wide-angle)
• G35 – 35mm f/2 Planar (general purpose)
• G45 – 45mm f/2 Planar (standard lens)
This range from 28mm to 45mm is commonly used for street, documentary, and travel photography.
Continuing the Exploration
With the release of the 28mm, 35mm, and 45mm conversion kits, Funleader and Mr. Ding mark a major milestone in the Contax G conversion project. While these three lenses represent a key stage, the team leaves open the possibility of developing conversions for other focal lengths in the future, continuing their mission to bring classic lenses to modern camera systems and keep vintage optics alive in the digital era.