I’m testing a Sigma 12-24mm F4.5-5.6 EX DG super wide angle zoom lens for Zoom Street. Initial results using a Nikon D90 have been impressive. This is one mean lens when you need extreme coverage. I’d heard a few complaints about flare being a problem, but haven’t had a problem.
On a full-frame DSLR the lens provides a 122 super wide view along the diagonal axis, pretty slick. Stay tuned for a complete report.