Delivering both smooth bokeh and fine sharpness, the FE 100mm f/2.8 STF GM OSS Lens from Sony is a short-telephoto prime featuring a unique, yet sophisticated optical design. Separating itself from other portrait-length lenses, this 100mm f/2.8 features Smooth Trans Focus (STF) technology, which uses an apodization filter to realize notably smooth bokeh with rounded out-of-focus highlights in both the foreground and background. Contributing to a high degree of sharpness and clarity, the lens also incorporates one aspherical element and one extra-low dispersion element to suppress both spherical and chromatic aberrations. Additionally, a Nano AR coating has also been applied to reduce lens flare and ghosting for greater contrast and color fidelity when working in strong lighting conditions.
Complementing the optics, this lens also sports a robust physical construction that is dust- and moisture-sealed for use in trying conditions. It is also an apt performer, and utilizes a Direct Drive SSM to afford quick, quiet, and smooth autofocus performance. A macro switching ring permits selecting between two focusing ranges, including a dedicated close-up range for working with subjects as close as 1.9' away with a 0.25x maximum magnification. Additionally, Optical SteadyShot image stabilization further contributes to producing sharp images when shooting handheld by minimizing the appearance of camera shake.
- Short telephoto prime designed for full-frame Sony E-mount mirrorless cameras, however it can also be used on APS-C models where it will provide a 150mm equivalent focal length.
- Optical design incorporates an apodization element that helps to improve the quality of bokeh. This element, which resembles a radially graduated ND filter that tapers from clear in the center to denser around the edges, produces more circular out-of-focus highlights for more pleasing selective focus and shallow depth of field effects.
- An aperture range of f/2.8 to f/20 is available, however the implementation of the apodization filter renders this range as T5.6 to T22.
- One extra-low dispersion element reduces color fringing and chromatic aberrations while one aspherical element controls spherical aberrations for improved clarity and sharpness.
- Optical layout has also been designed to reduce peripheral highlight distortion due to vignetting in order to achieve rounder out-of-focus highlights in both the foreground and background.
- A Nano AR Coating has been applied to reduce surface reflections, flare, and ghosting for increased contrast and color rendering in strong lighting conditions.
- A Direct Drive Super Sonic wave Motor AF system and internal focus mechanism provides quick, quiet, and precise autofocus performance and also contributes to more natural, intuitive manual focus control.
- A macro switching ring allows you to choose between two focusing ranges: 2.8' to infinity or a closer range of 1.9-3.3', which also offers a 0.25x magnification at minimum focus for working with close-up details.
- Customizable focus hold button on lens barrel can be used to hold the focusing position, or can be set in-camera to control a variety of additional lens functions.
- Optical SteadyShot image stabilization helps to minimize the appearance of camera shake for sharper imagery when shooting handheld with slower shutter speeds. This stabilization system can also be combined with select camera's sensor-shift type image stabilization for more effective control of camera blur.
- Manual aperture ring can be de-clicked for smooth, silent aperture switching to benefit video applications.
- A dust- and moisture-sealed design better permits working in inclement conditions and rubberized control rings benefit handling in colder temperatures.
- A rounded 11-blade diaphragm further contributes to a pleasing bokeh quality when employing shallow depth of field techniques.