Canon EF 24mm f/2.8

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24mm lenses are the entry into ultra-wide angle photography and this lens is the ideal starting point. It is extremely sharp and offers superior correction of linear distortion, and its f/2.8 aperture makes it easy to use with slow, fine-grain films or in low light. It focuses as close as 10 inches (25cm), and for many photographers gives the ideal combination of a wide-angle "look" without excessive perspective distortion.

Another superb ultra-wide-angle choice, with floating optics for superior performance throughout its focus range and a fast f/2.8 aperture that makes it a great alternative to a zoom lens for low-light shooting. Its rear-group focusing system reaches down to less than 10 inches (0.25m).