Constant f/4.5 throughout the zoom range and internal zoom design... Presenting a new paradigm for telephoto zoom lenses
Sony appears set to open a new chapter for its premium lens lineup, the G Master (GM) series. According to major foreign media outlets, including SonyAlphaRumors, Sony is expected to unveil the new 'FE 100-400mm f/4.5 GM' lens at an upcoming product launch event.
◇ Realization of World-First Constant f/4.5 Aperture Across All Focal Lengths The most notable feature of this new product is the shift away from the variable aperture (f/4.5-5.6) of existing models to a constant f/4.5 aperture throughout the 100mm to 400mm range. This is expected to be a groundbreaking change for sports and wildlife photographers who require stable exposure without shifts in aperture values. This is interpreted as a reflection of an unprecedented and unique optical design.
◇ 'Internal Zoom' Design Secures Both Balance and Durability The changes extend beyond performance to the physical form factor. This lens is reported to employ an 'Internal Zoom' mechanism. Thanks to a design where the lens barrel does not extend externally during zooming, maintaining balance when using a gimbal is much easier, and sealing performance against dust and moisture has been significantly enhanced. The total length is expected to be approximately 318mm, similar in physical size to the existing FE 200-600mm G lens.
◇ A New 'Ultra-Premium' Lineup, Not Just a Simple Successor Industry insiders view this lens not as a simple second-generation (Mark II) replacement for the current 100-400mm GM model, but as an 'entirely new lineup' in a higher tier. The estimated price is likely to be set at approximately €5,000 (over 7.5 million KRW), directly targeting the high-end professional market.
◇ Summary of Key Expected Specifications
- Aperture: Constant f/4.5 across the entire range
- Structure: Internal zoom design with no barrel extension
- Performance: Equipped with next-generation AF motors for significantly faster focusing speeds
- Release Date: Scheduled for mid-May 2026
[Editor’s Note] "The leaked specifications for the FE 100-400mm f/4.5 GM are truly worthy of being called a 'game changer' for telephoto lenses. In particular, overcoming the limitations of variable apertures to maintain a constant f/4.5 while adopting an internal zoom design reveals Sony's strong commitment to capturing both shooting convenience and output reliability. While the high price tag may be a barrier to entry, it is expected to become an irreplaceable, ultimate tool for professional photographers who must capture fleeting moments."