5 out of 10 points and not recommendedConstruction, HSM, comes with nice caseVery soft wide open
Bought this lens as an alternative for my EOS 5D/ EF 15-2.8 Fisheye combo. Tested the lens on my EOS 40D and was very disappointed by the image quality wide open. The image was far to soft, beyond recovering with Unsharp mask.reviewed January 31st, 2008 (purchased for $800)
This is really a pity because the construction and HSM autofocus is superior to the Canon EF 15-2.8.
The lens is larger and quite a bit heavier (475 gr, 330 gr for the EF 15-2.8)
Stopping down to f8 gives a comparable result with the Canon EF 15-2.8 (also stopped down to f8)
Images made with this lens are a bit warmer (typical Sigma, one likes it or not, its a matter of taste) than the images made with the EF 15-2.8
Also noticeable is the slight reduced angle of view (167 degrees instead of 180 degrees for the EOS 5D / EF 15-2.8 combo).
The lens comes with a very nice padded case.
The lenscap consist of two parts (cap and a kind of ring) and fits very tight (Canon might learn something here...) Leaving the ring on the lens gives a nice circular effect on the resulting image (not quite like a circular fisheye but still this is a nice feature).
At the back of the lens is a slot for gelfilters (a metal plate to cut the filters in the right size is also provided with the lens)