Canon EOS 15mm Fish eye 2.8

The heavy barrel distortion from the 15 Fisheye creates a special effect that is liked by most people (until it is over-used of course). With digital capture, we can now use fisheye-to-rectilinear conversion software to create a corrected picture equivalent to what a 12-13mm rectilinear lens would yield. This is great - but it takes some extra post-processing work and requires some knowledge of what the end-result will look like when capturing the shot.