Summary: Nobody can deny that this interesting fisheye lens performs well, is built well and offers a unique two lenses in one solution for full frame camera users, and users of multiple Canon sensor formats.
Pros: Excellent sharpness, in the centre of the image area, Superb build, Unique zoom design effectively gives full-frame users two lenses in one, Useful for owners of multiple Canon camera formats
Cons: Expensive, No way to lock the lens at either end of the focal range, High CA levels towards edges of the picture area
Canon EF 8-15mm f/4 USM L Fisheye - Review / Test Report
17 February 2012
Conclusion: The Canon EF 8-15mm f/4 USM L Fisheye is a more than welcome addition to the Canon lens lineup. The combination of circular and full frame fish-eye in a single lens is a unique offering in the market. It is also capable of delivering technically decent results.
Summary: The Canon EF 8-15mm f/4L Fisheye USM remains a slight oddity and yet an extremely fun lens to use. The optical quality is impressive for such a wide lens and the performance is exceptional, from the autofocus to the weather-sealing.