For a single lens, I would go with a wide-ish zoom. Something like a 17-55mm. To make it suitable for dark conditions, I would also go with a zoom offering an aperture of f2.8. This will let a lot of light in, and will give you good flexibility after dark.
That is a very flexible lens that will cover most shooting situations.
![75.gif](http://www.smakynet.com/images/75.gif)
Super advice...the lens makes the camera.
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