The GFX ETERNA 55 uses the custom-built sensor of the GFX100 II.
One of the most significant differences from still cameras is the presence of a cooling fan. Because the GFX ETERNA 55 is designed for filmmaking, it is naturally expected to record continuously. This results in heat generation from the constantly active sensor, and effective heat dissipation is crucial. The goal was to enable unrestricted recording time. To meet this goal, additional heat-dissipating metal components were incorporated, and the internal structure was redesigned—distinct from that of still cameras—to withstand long takes.
To further enhance usability for filmmakers, a new dual-base ISO system was developed, allowing ISO 800 and ISO 3200 to be individually fixed and controlled. Additionally, the GFX ETERNA 55 is equipped with native G mount support and a PL mount adapter, enabling compatibility with a wide range of lenses—just like the GFX100 II—making it possible to shoot in various formats. One particularly notable new feature is the 48fps open gate mode. This newly designed drive mode utilizes the sensor’s full light-sensitive area of 43.63mm × 32.71mm, enabling 4:3 aspect ratio shooting with greater vertical resolution and a three-dimensional feel to the image.
The first step in adapting the sensor for filmmaking use was the inclusion of an optical low-pass filter (OLPF) in front of the sensor. The OLPF helps align the separated RGB Bayer pattern more precisely, delivering clean and accurate color information to the sensor. Traditional film captures RGB information across three separate layers, and this low-pass filter emulates that film-like look, achieving a similar visual softness while reducing moiré and false color artifacts.
Another major enhancement is the integration of an internal electronic ND filter designed for large-format sensors. It covers a density range from ND0.6 to ND2.1, enabling seamless light reduction from 2 to 7 stops, with five stops of smooth transition in between. Development of the electronic ND filter began a year prior to the development of the GFX ETERNA 55, with repeated prototyping and input from other departments. One of its standout features is the ability to finely modulate light attenuation in precise 0.05-stop increments (ND0.015). This level of granularity allows nearly imperceptible transitions in exposure—a key strength of the GFX ETERNA 55. Achieving this required detailed individual tuning of each unit, a process Fujifilm has routinely employed since the days of still cameras. Size was another challenge. Larger components are more prone to distortion, so extensive testing was conducted to integrate the system without compromising image quality. Ultimately, it was the fusion of analog and digital expertise that made the development of the GFX ETERNA 55 sensor a success. We hope creators will fully explore the beautiful cinematic expression this camera enables—especially by making the most of its low-pass filter and electronic ND filter.
