Sigma 8mm f/3.5 Fisheye

A comnplete 180 degree field of view circular fisheye lens on a full frame camera such as the 5D or 1DsII. A lesser fisheye on a crop frame camera like the 40D or XTi. It gives interesting (bizarre some say) effects and is sometimes used for scientific applications because it provides a consistent angle throughout its 180 degree field of view. OK, well it could be used for scientific purposes but mostly its used to give weird ’cow’s eye view’ scenics: think about it – you take a picture, turn around and take another picture, and now you’ve got a 360 degree panorama.

Roger’s take: Full disclosure here: I’m not a fan of the fisheye look, especially the full circle fisheye look. But I will say this is a sharp lens with a huge depth of field. And the images are incredibly panoramic when ‘defished’ in software, which is what I do with them mostly. The depth of field makes autofocusing almost unnecessary, and the image is very sharp in the center (not so much on the edges, especially after software defishing if that’s what you choose to do). There’s some chromatic aberration and edge vignetting to deal with in software also.

One point I’ll warn everyone about: the dark coating used on all of the 4.5 and 8mm Sigma fisheyes tends to flake off. It has absolutely no effect on image quality but its apparent cosmetically and has occurred on every copy we have.