Sony FE 100mm f/2.8 STF GM OSSDelivering both smooth bokeh and fine sharpness, the FE 100mm f 2. 8 STF GM OSS from Sony is a short telephoto prime featuring a unique and 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. Optical design incorporates