The Bokeh Dreamer with Ultra-sharp image and Silky smooth Bokeh. Featuring an unique STF (Smooth Trans Focus) optical design. This award-winning lens incorporates an apodization (APD) element next to the aperture which resembles the function of an ND filter. It gradually reduces the amount of light transmitted towards the periphery to produce a soft, natural and beautifully diffused out-of-focus rendition. The chromatic aberration has also been controlled to the minimal.