I am looking at 17-70 range. This a good range for general walkabout photography
In that range, I can only think of one lens.
The Sigma 17-70 F2.8-4.5. But its still not a fast lens.
Another option which I have extensive experience is the Tokina AT-X 280 AF F2.8
This is a fullframe lens. I use this with my D700.
I was lucky to have a very sharp copy of this lens.
But since I sold my D700 and retained my DX bodies, I also sold it and went for the Nikon 17-55 F2.8
Since you are in Singapore, Im sure there are a lot there you can get. New and Used.
I suggest you try it first and be sure to have a sharp copy.
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