Sigma 8mm f/3.5 EX DG CIRC FISHEYE LNS f/CAN
Sigma's circular 8mm fisheye gives images a rounded look for unusual effects. Designed for full frame cameras, this lens can focus on objects as close as 5.3 inches away. Sigma has used several different lens coatings to ensure color accuracy while reducing unwanted reflections. The autofocus is accurate, since manual can be difficult to get exact because of the wide perspective. The rounded front of fisheye lenses doesn't allow for using traditional filters, but a holder at the back still allows you to use colored gels. Nicely compact, the lens weighs less than a pound.