http://www.nikonchat.com/nikkor-f2-8/
which will you choose? 28 to 75 or 18 to 200?
to be chosen for daily use? a tamron 28-75 f2.8 or Sigma 24-70mm F2.8 EX DG MACRO? because I have now a 18-200mm Nikkor f3.5-5.6, I continue my Nikora or worth a constant exchange of f2.8?
18-200 VR lens that very much lives on my camera. That's what I keep on when you put the camera away so you will be able to grab it and get almost any shot that is urgently required. That's what lock and load, I'll be in somewhere where I'm not sure what they are and not feel like playing with the lens swaps. I have the DX 17-55 mm f / 2.8 and is a nice goal. I mount it when counts image quality and still want the flexibility of a zoom, not knowing the extent of 18 to 200. In its digital SLR, you'll find that the 28-75 does not give you much at the wide end. It is basically a "normal" mild-tele zoom. I'd miss the end of 18 mm. Looking in my crystal ball these days, I can see that I avoid buying any more or cropped DX format similar ("digital") lenses. I do not know if you're buying another body again, but if I do I think there's a good chance it will be a full-format sensor. Unless you are 100% sure you never own a FF camera, I suggest you consider same. This would mean that the 17-35 f/2.8 DX instead of 17-55, although I admit that 35 mm is much shorter than 55 mm and I use the long end of the lens. http://www.bhphotovideo.com/c/product/186250-USA/Nikon_1960_AF_S_Zoom_Nikkor_17_35mm.html The 24-85 f/2.8-4.0 is not a fixed-aperture lens, but start at f / 2.8, and only loses a stop at the telephoto end. It is popular as a target pro general use. It is much cheaper, too. Http: / / www.bhphotovideo.com/c/product/207358-USA/Nikon_1929_Zoom_W_A_Telephoto_AF_Zoom.html It costs a little more than the Sigma and Tamron that you mention, but I think it's worth a look, Fhotoace based on feedback from past years.
Canon 550D + Nikkor 55mm F2.8 + Nikkor 180mm F2.8
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