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Rather Nikkor 17-55mm f/2.8 or Nikkor 24-70mm f/2.8?
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For portraits (and portraits only) I prefer to use an AFS Nikkor 50mm f/1.4G. It gives better image quality in a much smaller and cheaper than any of the package lens. It is open f/1.4 also ensures that its funds are well out of focus while keeping the subject in focus. If you insist on the lens between the two, I would get the 24-70mm for portrait a D3000, due to its longer focal length. However, the extreme width of 24 mm is not really wide enough for other topics such as architecture and landscape so the 17-55mm is probably even more versatile and useful for most people. (And if you only wanted to shoot pictures, I'd take 2 or 3 lenses primary end lighter and cheaper than any of those lenses too).
AF-S NIKKOR 24-70mm 1:2.8G ED Nikon Lens
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