Utilizing the Shift feature, lens rotated so the shift is pointing up, thereby blurring out the bottom half of the image. You could apply just a gradiant guassian blur via Photoshop, but I doubt you could accomplish the wide open (F2.8) light out-of-focus blur in the same way.
45mm, F2.8, iso 100, 1/6 Second, Tungsten WB
This is oriented in Landscape, but the whole base of the lens rotates so you can have it shift in any direction. The above picture was taken in portrait (obviously), so the base would have been rotated.
45mm, F2.8, iso 100, 1/6 Second, Tungsten WB
This is oriented in Landscape, but the whole base of the lens rotates so you can have it shift in any direction. The above picture was taken in portrait (obviously), so the base would have been rotated.