The Master of Bokeh
Introducing the Sony FE 100mm f/2.8 STF GM OSS, a short-telephoto prime lens renowned for its exceptional optical design. Setting itself apart from other lenses in its class, this 100mm f/2.8 lens incorporates the innovative Smooth Trans Focus (STF) technology. By employing an apodization filter, it achieves remarkably smooth bokeh with rounded out-of-focus highlights, creating a unique and captivating visual aesthetic in both foreground and background.
Smooth Trans Focus
The optical design integrates an apodization (APD) element that enhances bokeh quality. This element resembles a radially graduated ND filter, transitioning from clear in the center to denser at the edges. As a result, it produces more circular out-of-focus highlights, delivering delightful selective focus and shallow depth of field effects.
While the aperture range spans from f/2.8 to f/20, the implementation of the apodization filter renders it as T5.6 to T22.
A rounded 11-blade diaphragm further contributes to the lens’s pleasing bokeh quality, especially when shooting with shallow depth of field techniques.
G Master Optics
G Master lenses prioritize both sharpness and bokeh quality, employing advanced optical designs and specialized elements.
One extra-low dispersion (ED) element effectively reduces color fringing and chromatic aberrations, while one aspherical element controls spherical aberrations to enhance clarity and sharpness.
The optical layout is meticulously crafted to minimize peripheral highlight distortion caused by vignetting, ensuring rounder out-of-focus highlights in both foreground and background.
A Nano AR Coating is applied to reduce surface reflections, flare, and ghosting, resulting in increased contrast and improved color rendering even in challenging lighting conditions.
Autofocus and Macro Switching
The lens utilizes a Direct Drive Super Sonic wave Motor AF system, delivering rapid, silent, and precise autofocus performance, while also providing a more natural and intuitive manual focus control.
An internal focusing design enhances focusing responsiveness and maintains a consistent lens length during operation.
A macro switching ring allows for two focusing ranges: 2.8′ to infinity or a closer range of 1.9-3.3′.
With a maximum magnification of 0.25x at minimum focus, the lens offers near-macro capabilities, enabling detailed close-up shots.
The customizable focus hold button on the lens barrel can be used to lock the focusing position or assigned in-camera to control various additional lens functions.
Handling and Physical Design
Optical SteadyShot image stabilization effectively minimizes the impact of camera shake, resulting in sharper images when shooting handheld with slower shutter speeds. This stabilization system can also be combined with select cameras’ sensor-shift type image stabilization for enhanced control over camera blur.
The manual aperture ring can be de-clicked for seamless and silent aperture adjustments, benefiting video applications.
With its dust- and moisture-sealed design, the lens is well-suited for working in inclement conditions, while rubberized control rings ensure comfortable handling even in colder temperatures.