Sigma 15mm on Canon 10D

I know there is the 1.6x factor with lenses on the Canon 10D so the

full frame fisheye Sigma 15mm lens should act as a 24mm lens. What

happens to the 180 degree field of view? Does the captured image

display without fisheye characteristics in full frame?

On my d30 (same 1.6x factor) the images had about the same FOV as a 20mm lens. This is due to the fact that a 15mm fisheye lens has a larger FOV than a 15mm non-fisheye lens. The fisheye's is the already mentioned 180 degrees, and a non-fish 15's is aprox 110 degrees. The 15mm fisheye creates an image with a decent ammount of corner "bending" distortion. But not nearly as much as the fisheye lens does on a film SLR.

I'd agree with Josh. You get a horizontal field of view about the same as that of a 20mm lens on 35mm film (which is about 85 degrees), though with moderate fisheye distortion. The distortion means you get a diagonal field of view greater than a 20mm lens on film (which is 94 degrees), but less than 180 degrees. If you look at my article on the <a href="http://www.photo.net/canon/10D/">EOS 10D</a> you'll see some shots taken with a 16mm fisheye lens. Used carefully the distortion is only there if you look for it!

<p>The distortion can be digitally corrected to some extent and with some quality loss, especially at the corners of the image as shown above.<div></div>

does any one have an example of an image taken with a 8mm circular fisheye on a DSLR w/ a 1.6x conversion factor... is there vignetting still?

Steve - For details and examples of an 8mm circular fisheye capture with a 10D see <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=005Jlv">this thread</a>.