For the guys asking about the Tokina and the 5D mmiii - http://www.stockhammedia.com/2012/10/19/tokina-11-16mm-f2-8-with-5d-mkiii/
Thanks a lot Cgdillan. Those shots cleared out some confusion. 15mm and 16mm looks very much usable. So, I got myself a uwa prime now lol.
no problem. yes very very usable. haha. yeah that's what it is for me =-) except I'd call it a dual focal length uwa prime.
The Tokina 15-16mm AT-X 116 Pro AF FX "DFL UWA" Prime lens for Canon EOS
+1 on that new lens name. Hahaha!