The Tokina 12-24mm f/4 is a very fine lens. Excellent color and very well built.
Sample photo:
http://www.jbs-blog.com/images/offsi...10-05-2311.JPG
It's the side yard of the chapel at Duke University in Durham, North Carolina, USA
It's an original full size photo from a Canon 20D using the Tokina lens - it's 3.8 meg in size
1/1000 sec f/7.1 ISO 200 Focal length of 12mm (that's on a 1.6x crop camera body ... so more like 19mm)
I love this lens!