This lens is one of my favorite primes. It is sharp and focuses as fast as any L lenses I own. The colors and contrast are great. It has a little bit CA (chromatic aberration) when used wide open in the extreme contrasty scenes.

It did extremely well in the 2005 and 2006 Renaissance Festival photo shoots. It was also used for indoor NBA games. On the 5D, it is not as long as it is on the 20D, perhaps, the 135 f/2 would be perfect. :)

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