Reduced Sized Wide-angle Lenses

I’ve updated my list of real estate cameras to remove the Canon 10-20mm and Sigma 10-20mm from being usable lenses with the Canon EOS 5D. Until Marc Lacoste pointed it out, I’d completely over looked the fact that these two lenses are two examples of the generation of smaller lenses designed to be used with only with DSLRs that have reduced sized image sensors. These lenses have a smaller image circle that works nicely with small image sensors but do not use the full 35x24mm sensor size of cameras like the Canon 5d, 1Ds, 1Ds II.

Marc also give us a link to his wide-angle camera list. He has some nice features like a table of focal length equivalences and links to detailed information. Check it out at:
http://marc.lacoste.googlepages.com/wideanglecameras
Thanks Marc.