Development Story vol.03: Newly Developed 35mm F4 Lens
The new 35mm F4 lens is a key factor contributing to the compact size of the GFX100RF.
By designing it as a single unit, we were able to shorten the back focus. The use of two glass-molded aspherical lenses allows for a smaller size while maintaining high resolution. Additionally, instead of using a focal-plane shutter, a leaf shutter— a first for the GFX series — has been integrated, further enhancing the compact design.
The forward-tapering silhouette of the lens was achieved by repositioning the focus-moving components toward the front, beautifully complementing the rangefinder style. This design creates an unobtrusive form that fits snugly in your hand when shooting.
There is no merit in large format photography if it compromises resolution for the sake of compactness. When we say that “compactness and high image quality coexist thanks to the advantages of a fixed lens,” many will recall the lens updated with the X100V. That design philosophy has been applied to this lens as well.
The 35mm (28mm equivalent in 35mm format) that captures everything in sight. To fully utilize this wide image, it is essential for the image to maintain sharpness even at the periphery. It is impossible to predict which part of the 100 million pixels will be most important. Generally speaking, the larger the canvas, the easier it is to conceal details. However, the GF lens is engineered to leverage the large format sensor of the GFX to resolve even the finest details with the same density as the X series. Even when enlarged, the details remain intact, allowing the lens to convey the subject’s texture and the atmosphere of the scene effectively. The development philosophy of GF lenses has remained steadfast, even with the single-unit design.
Photo by Reuben Wu
With a fixed lens, there are no mount restrictions, greatly enhancing the freedom of optical design. We pursued superior image quality with high precision, utilizing two aspherical lenses to suppress spherical aberration and field curvature. Additionally, we developed a new Nano GI coating optimized for lenses with larger curvatures due to their compact size, significantly reducing reflectance in peripheral areas and minimizing ghosting. This results in consistent image quality not only at the center but also throughout the periphery.
Photo by Kirsten Luce
The lightness, a characteristic of rangefinder-style cameras, is achieved not only through compactness but also through advanced autofocus (AF) technology.
However, the incidence angle is tighter in fixed-lens models compared to conventional GFX series models due to their smaller size, resulting in less light required for phase detection AF. The latest algorithm, praised in the GFX100S II, has been fine-tuned to optimize performance for the fixed-lens GFX100RF. Furthermore, the DC motor ensures high speed and torque. The fixed-lens design and precise adjustment maintain seamless communication with the lens mount, allowing for smooth movement of the focus ring during manual focus (MF).
Photo by Giulio Di Sturco
Optimization through motor control, grease adjustments, and enhanced component rigidity physically reduces vibration. This results in a powerful DC motor that precisely moves large lenses while maintaining the same low operational noise level as the X100VI. Additionally, it features a built-in ND filter and a minimum focusing distance of 20 cm from the lens tip, ensuring exceptional image quality and operational convenience.
