Sony 135mm f/2.8 (T4.5) STF SAL-135F28
(From Sony lens literature) Create smooth, aesthetically pleasing out-of-focus backgrounds that make sharp-focus subjects stand out more vividly with the Sony SAL-135F28 special purpose lens.
A unique telephoto lens for smooth, natural focus effects in foreground and background. This advanced STF (Smooth Transition Focus) telephoto lens incorporates an apodization optical element that distributes light rays to create smooth, aesthetically pleasing out-of-focus backgrounds that make sharp-focus subjects stand out more vividly. Mounted on the Sony a (alpha) DSLR-A100 camera, this lens provides a 200mm focal length (35mm equivalent).
Smooth Transmission Focus: While subjects remain in sharp focus, out-of-focus backgrounds or foregrounds are blurred smoothly and evenly with gradation that thickens toward the edges of the frame for a pleasing aesthetic effect.
Transmissive Brightness: After light passes through the apodization element, the lens aperture of f/2.8 yields a T (transmissive brightness) equivalent of 4.5; a manual aperture ring can adjust T setting from 4.5 to 6.7.
Wide Focus Ring: The dedicated manual focusing system is controlled by a wide focus ring that's comfortable to hold and gives you a solid, hands-on feel for pinpoint focusing of your subject.
Circular Aperture: Because aperture blades form a near circle at the wide openings used for low-light shots, spot-light sources have a pleasing circular defocused effect.
Sony 135mm f/2.8 (T4.5) STF SAL-135F28 User Reviews
9 out of 10 points and recommended by DonnyTam (2 reviews)Uniquely smooth Bokeh, dual aperture control.T4.5.. less light fall on sensor, the hood doesn't locked properly.
amazing Bokeh rendering. a bit tough to use on APSC camera. work like charm when pair with A99 with Peak Focus.reviewed November 26th, 2012 (purchased for $956)