SkipD wrote:
Simon, one thing that you should understand is that a zoom lens with a zoom ratio significantly exceeding 3:1 (3:1 example: 50mm to 150mm) is likely to be an optical compromise at best.
Most high quality zoom lenses have a zoom ratio of 3:1 or less. Canon "L" lens examples: 16-35mm, 24-70mm, 70-200mm, etc.
The 18-200mm lens you are looking at has a zoom ratio exceeding 10:1.
Simon, one thing that you should understand is that a zoom lens with a zoom ratio significantly exceeding 3:1 (3:1 example: 50mm to 150mm) is likely to be an optical compromise at best.
Most high quality zoom lenses have a zoom ratio of 3:1 or less. Canon "L" lens examples: 16-35mm, 24-70mm, 70-200mm, etc.
The 18-200mm lens you are looking at has a zoom ratio exceeding 10:1.
I believed this too until I saw pictures taken with the Sigma 50-500 over at www.birdforum.net
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