Funleader Contax G35 Leica M conversion (Planar 35mm f/2 T* lens) v2.0 vs v1.0 comparison





Here are the improvements in the new Funleader Contax G35 non-destructive conversion kit V2.0 for Leica M-mount (Planar 35mm f/2 T* lens) compared to the previous v1.0 release (get 5% off with code LEICARUMORS):

Following strong interest in the original non-destructive conversion (quickly sold out last time), V2.0 introduces mechanical and exterior refinements while preserving the original Contax G35 optical block. Updates include a reworked internal structure with smoother focus damping, tighter tolerances, and improved long-term stability, along with subtle exterior design refinements for better visual integration with the Leica M system (see previous coverage).

Contax G35 Conversion Kit V2.0: A Structural Evolution of a Proven System

The Origin of the G35 and G45 Conversion System

The Contax G system, introduced in the 1990s, remains one of the very few rangefinder platforms to have achieved autofocus. Developed jointly by Contax and Carl Zeiss, the system was accompanied by a series of compact T*-coated lenses known for their optical consistency and mechanical precision. Among them, the 35mm and 45mm focal lengths became the most widely used, offering a balanced combination of field of view, resolution, and portability.

Even after the Contax G camera bodies faded from mainstream use, these lenses continued to attract attention from photographers. The G35 in particular, with its natural perspective and stable rendering, has long been regarded as a strong match for the Leica M rangefinder system. However, early conversion methods often required irreversible modifications to the original lenses, compromising their integrity and long-term value.

In response to this, the Mr Ding development team, in collaboration with Funleader, introduced the first non-destructive Contax G35 conversion system in 2019. Using a dedicated conversion helicoid, the original optical block could be installed without any permanent alteration, enabling full Leica M rangefinder coupling and a shooting experience comparable to native M-mount lenses.



In 2021, the same engineering approach was extended to the G45, with further refinement of exterior design to better match the visual language of Leica M cameras.

Why G35 V2.0 Was Developed

After the first-generation G35 conversion kit was released, it accumulated several years of real-world use across a wide user base. The feedback was not focused on optical performance—which remained unchanged—but on mechanical behavior: focus damping, long-term stability, and how naturally the converted lens integrated into the Leica M system, both mechanically and visually.

Based on this accumulated experience, the Mr Ding team initiated the G35 V2.0 project in 2024. The goal was not to change the original non-destructive concept, but to refine it through a more robust mechanical structure and improved manufacturing detail.

Mechanical Refinement and Focusing Feel

The most important update in V2.0 lies in the internal focusing mechanism.

The transmission system and damping curve have been redesigned to provide smoother, more consistent resistance throughout the entire focus range. This improves control, especially when fine-tuning focus at wide apertures or close distances.

Rather than being a specification-driven upgrade, this change is felt directly during use: focus movement is more fluid, more predictable, and more stable, contributing to greater confidence in real-world shooting.

Exterior Design and Visual Integration

The V2.0 version also introduces a series of subtle exterior refinements designed to improve visual coherence when mounted on Leica M cameras, including:

– Repositioning of the 35mm focal-length marking

– Updated typeface on the lens barrel

– A redesigned focusing lever

– Modified grip pattern on the barrel

These changes are not intended to make the lens look “new,” but to allow it to blend more naturally into the Leica M system rather than appearing as a separate conversion component.

About the Aperture Behavior

During the mechanical redesign of V2.0, the internal structure was optimized to achieve improved focus damping and long-term mechanical stability. As a result of this redesign, one compromise was introduced due to the structural limits of the original Contax G optical unit.

When the aperture is set to f/16, the effective aperture is approximately f/13. When rotating back from f/16 toward f/11, the aperture remains at f/13 until the ring is returned from f/8 to f/11.

This behavior is inherent to the optical and mechanical constraints of the original G35 lens design. Given that f/16 is rarely used in practical photography, the development team chose to prioritize focus feel and mechanical reliability over maintaining the full aperture travel.

Conclusion

The Contax G35 Conversion Kit V2.0 does not represent a change in direction, but rather a refinement of a proven system. By preserving the original optical structure while improving mechanical precision and exterior integration, V2.0 allows this classic Zeiss lens to function more consistently and confidently within the modern Leica M environment.

It remains faithful to the original non-destructive philosophy, while delivering a more mature and coherent user experience.

Additional information:

Key details

Specifications

Introduced in the 1990s, the Contax G system was one of the few 35mm camera systems to combine rangefinder viewing with autofocus operation. Developed jointly by Contax and Carl Zeiss, the system featured a lineup of Zeiss T* coated lenses covering a wide range of focal lengths. Among them, the 35mm and 45mm lenses became the most popular choices thanks to their compact size and balanced optical performance.

The G35, based on a classic Planar design, offers a natural field of view well suited for documentary and everyday photography, while the G45 is known for its high resolution and focused rendering. Both lenses remain highly regarded for their consistent and reliable image quality.

Design Concept

As digital photography became dominant, Contax G camera bodies gradually fell out of regular use, but the optical value of G-series lenses has never been overlooked. Many G-series users are also Leica M photographers, and the G35 in particular has long been considered a highly suitable focal length for the Leica rangefinder system.

Earlier conversion methods often required irreversible modifications to the original lens structure, compromising both integrity and long-term value.

In August 2019, Funleader collaborated with MrDing Studio to introduce a non-destructive conversion solution for the Contax G35. The goal was to preserve the original optical assembly while enabling practical and intuitive use on Leica M cameras. By installing the original optical block into a dedicated Conversion Helicoid, users with basic mechanical skills can complete the conversion and achieve reliable rangefinder coupling, resulting in an experience close to that of native Leica M lenses.

Building on this approach, Funleader released a non-destructive conversion solution for the Contax G45 in May 2021. In addition to preserving the optical design, the external appearance was refined with vintage-inspired elements to better integrate visually with the Leica M system.

Technical Notes

Due to conservative demand estimates at the time of its initial release, the first-generation G35 conversion kit sold out quickly. Over the following years, Funleader continued to receive inquiries regarding a potential reissue. Based on accumulated user feedback, the decision was made to relaunch the G35 conversion kit in 2024 with substantial mechanical improvements.

The new generation features a significantly revised internal structure, with particular emphasis on focus damping and mechanical smoothness. When operating the focus lever, users will notice a more fluid, consistent, and controlled movement, enhancing precision during actual shooting rather than focusing solely on specification completeness.

Compatibility & Notes

  • Designed for use with original Contax G optical assemblies, with no optical modification.
  • Fully supports rangefinder coupling on Leica M cameras.
  • When the aperture ring is set to f/16, the effective aperture is approximately f/13.When rotating back from f/16 to f/11, the aperture remains at f/13 and must be reset by rotating from f/8 to f/11.

This behavior is caused by structural limitations of the original optical assembly. After evaluation, priority was given to improved focus damping and overall handling, as f/16 is rarely used in practical shooting scenarios.







The new Funleader Contax G35 non-destructive conversion kit V2.0 is now back in stock (Planar 35mm f/2 T* lens)