Lenses

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Cons: nothing

Pros: very, very sharp lens, no remarcable CA's,use it for product photos

Summary: highly recommanded for all macro photographers

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Cons: Quite noisy and slow AF missing HSM, lens hood is not bayonet.

Pros: Super sharp lens (even more so than tamron 90 2.8 macro that also have had). Very well built, good bokeh to 2.8 and 4.0, absence of longitudinal chromatic aberrations.

Summary: Perfect for macro and portrait. I usually use for my panoramic photos by the almost total absence of distortions of all kinds. Spectacular.

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Cons: autofocus too often not correct at all (Canon 5DII), particularly at normal distances manual focusing ring much too fast, and inaccurate slight magenta tendence

Pros: very sharp at all apertures, distances as good as my Leica Elmar R4/100, Summicron R50, Elmarit R2,8/90

Summary: very good price/quality keep attention on autofocus

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Overall

Cons: none

Pros: my sharpest lens, extremly sharp!, build like a tank, nice outfit, softpouch, prize

Summary: a clear winner!

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Value for money
Overall

Cons: bad autofocus

Pros: macro

Summary: i am not a fan of this lens.

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Overall

Cons: none

Pros: the sharpest lens in my bag and in many stores.... nice bokeh and buildings, fair price, no faults

Summary: A real "Big Boy", one of the very best lenses around, perfect for macro and portrait

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Overall

Cons: HSM would be nice since focus ring moves in AF mode. Also the lens would be totally silent (it's not noisy though). Aperture blades are not rounded which can lead to nervous backgrounds in some very challenging cases.

Pros: Extremely sharp from corner to corner wide open and in full frame! Many tests also say that it's probably the sharpest consumer lens at the moment. AF is reasonably fast in normal range with limit switch. Lens is also built like tank.

Summary: Even with few minor cons, I think this lens is extremely good, especially when you consider the price. If Sigma added HSM and made the aperture blades rounded, I would be first in the line to upgrade.

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Overall

Cons: no HSM short working distance in 1:1 magnification

Pros: excellent image quality, great for portraits, macro and panoramas. the best lens in my bag

Summary: very versatile lens (70mm is almost the normal angle of view on FF), great value