SLR Gear has a good analytic review set for lenses. Canon is a focus here, but they have Nikon too of course. Unlike many reviews, this one is quite quantitative with good recommendations for what aperture and focal length to use for maximum sharpness:
Canon EF 100-400mm F/4.5-5.6L IS USM. Image quality 8.61/10. Best results at [...]
Canon lense quality
September 28th, 2008 · No Comments · Geek
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