Originally posted by BeerBelly @jsherman999: I'm not excluding the possibility that the sample I had for my Nikon cam was a bad one....but on the D90 it was sharp...on a D800 it again wasn't. All the tests show that the lens loses sharpness with higher resolution sensors. This is a dxo link where they tested zoom lenses with the D7100:
Best Zoom models for the D7100 - DxOMark. The version of the lens discussed here gets a 6 in sharpness, while the newer version (VC USD) gets a 16. It's like my own findings. I'm not trying to convince anyone into anything, just trying to help stating what I personally experienced.
K-r @ 200mm @ 2.8
K-30 @ 200mm @ 3.2 (same sharpness as above)
D7100 @ 200mm @ 2.8 (low contrast, aberrations, softness)
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In your examples it looks like you're comparing a higher-resolution sensor at a varied magnification factor, in which case the higher-res image is always going to look 'softer'. Regarding that DxO test, I think they had some odd issues with that test or sample on DX, which is reflected in those comments if you read - here's the non-VR 70-200 2.8 on the FF D800, it ranks up there just below the $2400 Nikon 70-200 2.8 VR II (and notice the price deltas in that list
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DxOMark quote: "
If you need a faster maximum aperture than f/4, then the Nikon 70-200mm f/2.8 VR II is the best in its class. If the Nikon is out of your price range, the $770 Tamron 70-200mm f/2.8 Di LD (IF) and the less-recent $1,850 Nikon 70-200mm f/2.8G IF-ED both score a very good DxOMark score of 26. In all areas, the two are seemingly equal, so your choice will eventually come down to brand loyalty and price as much as any image quality concerns"
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At $750, you can't go wrong IMO.
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