what lens to buy for street photography and close up portraits?

Hi,

I shoot street photography with a Canon 17-55 EF-S 2.8. It fits all my needs. It isnt an L lens so maintaining-wiping the exterior, barrel, with a microfiber cloth is part of my typical activity. I've had it over a year and dust hasnt been an issue.

Dave

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http://www.steadyhandimagery.com