Lenses

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Cons: Not very good @ 17mm f2.8: distortion, vigneting, but considering the price. Focus can be noisy.

Pros: Quite sharp for a lens in that category. Been able to do close-up is very usefull.

Summary: This is a great walk around lens. I have been using it on an EOS 20D and an EOS 50D. It is really much better than what the price suggest.

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Cons: Very poor IQ wide-open, occasional focus misses at 70mm in low light, high barrel distortion at 17mm (my 10-20mm is much better).

Pros: Good build quality, very good IQ. Sharpness is superb from f/4 and up, at f/5.6 reaches the level of my 50mm f/1.8 D prime at the same aperture. 17mm is the weakest spot, but from about 24 to 50mm IQ is just fenomenal. Outside this range there's a lack of constrast and sharpness at the corners. Very very fast AF, no CAs at all.

Summary: As long as f/2.8 isn't used, it's an excellent performer. No optical issues whatsoever except for high barrel distortion at 17mm (curved lines on buildings, etc.). Great substitute for a kit lens!

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Cons: No VR

Pros: Excellent build quality Excellent close focus ability Wonderful versatility Very reasonable price No focussing issues Nice and light Nice and sharp Smooth operation

Summary: This lens works just fine as a general walk around lens and I have never found any significant practical or optical shortcomings to speak of. It has all the zoom range I need 90% of the time. It is also a very useful, sharp macro lens - especially for a zoom. This is one of the best kept secrets in photo land.

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Cons: No

Pros: Useful range; decent build quality; good at low light conditions; good "macro" function.

Summary: A good lens to replace the kit lens, a bit better IQ than the kit, it also adds some more range. Very sharp when stepped down. Great IQ for its price.

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Cons: F2.8 is only for emergencies! Very soft edges raises the thought - why have F2.8 if it is as weak as that.

Pros: Generally great image quality, good colour tones and nice contrast. Lens is sharp from around 4.5 onwards 17mm is slightly better/more usefull than 18mm and distortions are generally low. Usefull close up ability - you can get very close - but not ideal for insects that scare easily as you have to get very close.

Summary: Nice walkaround lens with good image quality throughout - except at f2.8

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Cons: Tubus whobbling a bit; my sample is slightly decentered, but nothing to seriously worry about; not sharp at all settings; no IS; dust gets into the lens

Pros: Very useful range; decent build quality; still good also at low light conditions; good "macro" function

Summary: A good walkaround lens, with some issues; good image quality if you know the right settings; good value for money; only real problems are the mediocre sealing and the missing IS.

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Cons: have not came across any yet

Pros: Qualiy for a reasonable price

Summary: would recommend

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Cons: no IS, the AF/MF switch is bad,the warm tone of colours,noisy focus

Pros: 1-Low chromatic aberrations 2-Quite sharp 3-low distortion 4-IQ

Summary: good lens to replace the kit lens

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Cons: cant really think of any at this price range

Pros: Love the range, very sharp, smooth operation, price, macro capability

Summary: much better lens than the kit lens for sure !! This is my carry around do anything lens. Its sharp and relatively fast at f2.8. The price is right too. I love that it offers macro as well, while it doesnt get to 1:1 it still works well in a pinch. Works well for landscapes and portraits. I'm growing quite fond of the Sigma line, the optics and colors achieved with thier product line is quite good for the money.

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Cons: First one was defected, fortunately Sigma switched it for new one.

Pros: Low chromatic aberrations. Quite sharp. Usefully range.

Summary: Good replacement for kit lenses.

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Cons: 1. no IS (or OS for that matter) 2. not HSM 3. a bit noisy but tolerable focusing system

Pros: 1. Compact and light weight 2. Great range 3. Macro capable 4. good build (actually better than I expected) 5. Versatile lens

Summary: This is a good lens to replace the kit lens, not only does it produce a bit better IQ than the kit, it also adds some more range. Very sharp when stepped down. Great IQ for its price. The jack of all trades but master of none. IQ, range, and compactness, nothing can beat it at this price range.

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Overall

Cons: Not EX, no HSM on Canon

Pros: Light, sharp, nice macro, useful range.

Summary: It is hard to find anything better for 350 $.