Camera House Samyang 7.5mm f3.5 Fisheye UMC II - MFT - Black
This 7.5mm fisheye lens provides a diagonal field of view of 180 degrees on a Micro Four Thirds camera There is no electronic coupling between this lens and the camera, so metering is performed by stopping down the aperture and focusing is performed manually. As fisheye lenses provide expansive depth of field, this shouldn't be too much of a deterrent, especially with the low price taken into consideration.
Price: $549.00 from Camera House
