Used Lens Buying Guide Rev. 3.0
 

A big advantage of using a SLR (Single Lens Reflex) or DSLR (Digital Single Lens Reflex) camera is the ability to swap lenses to suit the job at hand. If you need to take shots of your buddies at a football game, you can use a telephoto lens to capture their finest moments from afar. And when you see a beautiful flower on the way back to your car, just replace the telephoto lens with a macro lens and you are set!
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*Source: TechARP (http://www.techarp.com/showarticle.a...o=194&pgno=0)*

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