I purchased a Canon EOS 50D with an EF-S 18-200 3.6-5.6 IS lens a month ago. After a month, I came to the conclusion that my 18-200 (I can't think of anything negative to say about it) f/4 of course, to shift from 200 mm to 105 mm, but it's already too short for me personally. In general, the contrast between the 18-200 and the 24-105 is very clear, and the 24-105 is the only one I own.
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