http://www.nikonchat.com/nikkor-18-55mm-review/
Which is better, Tamron or Sigma?
I've been using the 18-55mm standard lens of the camera (I have a Nikon D40), and I wanted a wider wide coordination for close-ups, macros, and for when I need one more catch. I have no money for a Nikkor or a gun as any I looked at were around £ 300 to 500. I was interested in a 70-300mm, and I looked at both a Tamron and Sigma. Both are exactly the same price, on all the characteristics Reviews were mixed them and what I expected, and that obviously reflects the price. Different people said different were the best, but if anyone has any of these glasses, his advice would be appreciated, and if I can see the pictures they have taken with him would be great. The two models were Sigma 70-300mm f/4-5.6 DG Macro Tamron 70-300mm Di LD Macro f4/5.6 However, if someone recommends the Sigma, I realized that there was another model of the lens, a little more expensive Sigma 70-300mm f/4-5.6 APO DG Macro Is it worth the extra Monet?
I've seen lenses Nikkor Sigma approach and sometimes even beat Nikkor (Sigma 105mm f/2.8 macro is sharper than Nikkor counterpart). I am Tamron still beat a Nikkor lens, or even come close to Nikkor. These two models are very similar to each other and no matter what you buy. Look for details service and buy the one that has better service network in your area. Sigma APO model has better color control (lateral) aberrations and worth the slight cost superior.
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