Image quality
Price
nice zoom range

vignetting at 18mm wide oben
soft corners at 125mm
focus hunting in low light

I bought this lens together with my EOS 350D, and it is my walk around lens. For the price and the zoom-range, the image quality is very nice. The lens has some weak spots, but if you know them you can work around. The problems are some vignetting wide open at 18mm, and soft corners at 125mm, and the auto focus has some problems in low light (focus hunting).
The build quality is ok. I'm using it since 3 years, which is visible on the lens, but it works still fine.

With the right settings this lens can produce very good pictures. Sometimes I'm amazed how sharp the pictures are, from a lens in this price class. This is also the reason why I still don't have a 18-50 f2.8, because the benefit would not be that big.

If you want a good walk around lens and the 17-70 or 18-85 are too short for you, this is the lens to go.

Customer Service

not needed

Best deal on wide.

noisy AF, i can live with.
im not a spy.

I finally bought this Sigma 18-125mm to be my everyday lens for use with my Sony A100, this lens will be stabilized on my Sony A100, that would helps on sharpness and anti shake, it works perfectly fine, i must have shot about 300 shots with it, most all images came out sharp and nice contrast, a little bit distortion at 18mm, but that is to be expected..on my Sony A100 this Sigma lens = 27-187mm, that is a very good all around range. The lens becomes much sharper from 35-125mm, good sharpness at 18mm, no purple fringes, great price, light and compact. But i must say the advantage of Sony DSLR is that all lens will be stabilzed when mounted, its the best feature on Sony, i havent had a single bad lens mounted on Sony yet. I can buy all the lesser lenses and they would work fine, i never have worried about buying over price VR and IS lens again, because Sony A100 has built-in Anti Shake in body.
This lens is still made in Japan with metal mount, comes with petal hood, uses 62mm filter size, farely fast AF, but a little noisy AF. But with 100$ i dont complain, just got compliments.
I havent got a bad Sigma lens yet, and i have had over 20 Sigmas lenses.
Sigma rules.

Customer Service

none.

Similar Products Used:

Canon 24-135mm IS, Nikon 24-120mm, Tamron 19-35mm, Promaster 19-35mm, Sigma 18-200mm.
But this Sigma 18-125mm is the best out of the bunch.

Focal range
Build

None known

I purchased this lens for it's focal range after being told it was a sharp lens and I have not been disappointed. I have used this lens for weddings, sporting team photography and it is ideal as a travel lens whilst on holidays. It is a very sharp lens and with the SR of the Pentax DSLR's I can get super sharp images down to 1/15th of a second. It compares very favourably with the Sigma 10-20EX and the 50-500 EX and in my opinion outshines the 28-70 EX. It is also comparative to the older Pentax primes which I own a few of. My wife always grabs this lens while on holidays and I am so impressed with it that I will be purchasing another one prior to our next holiday for me to use.

Customer Service

Not had to use as yet

Similar Products Used:

Sigma 10-20EX, 50-500EX, 28-70EX
Pentax 50mm/2, 55mm/1.8, 28mm/2.8, 200mm/4

Looks and feels nice

The barrel distortion was horrible @18mm
Quite alot of vignetting @18mm and on the top end
Heavy lens.
Dont rely on the camera to autofocus with this lens.

Just yesterday I bought a Sigma 18-125mm F3.5-5.6 DC to replace my kit lens for a good inexpensive walk around lens. Took it our of the box and fired 1 shot to compair it to the kit lens. To my susprize this lens was horrible compaired to the kit lens. The image was so out of focus it wasnt even funny. Both were taken from the same spot and both was at f3.5 1/200 sec and ISO 100 with Autofocus on. I even went as far as to stomp it down to f4 through f9 and the kit lens was still sharper. So needless to say, it went back to the shop the the salesman tried it on another camera. Samething happened. Then he tried another lens, thinking the first one might be bad. Well it was worse than the lens I brung back.

Long story short. I returned the lens. I know Sigma makes some very good lenes, but this is not one of them.

Great sharpness, range, build quality. Colors are rendered vividly and accurately.

Focus a little on the slow side and noisy. But it's livable.

I bought this lens after reading many, many reviews from various sources. I must say that this lens has exceeded all of my expectations. I have read that at times Sigma may have QC issues with some of their lenses ie. front/back focus problems. I thoroughly tested this lens on my D70s when I first bought it to make sure my copy was not one of those. In fact, focus was spot on in each and every case and among many different lighting conditions and focal lengths. Very well done Sigma. Next comes the sharpness. Most make comparisons to to top of the line L lens or primes or what have you. Not right. This lens is not intended to compete with top quality glass. Lets face it - price does reflect quality. This is not an expensive piece of glass, but the value is fantastic. My copy is VERY sharp, if stopped down a couple of notches. Even at wide open, it does very well producing good sharpness, but with a slight fall-off in the corners. Vignetting is all but non existent except at 18-22 or so. Even so, easily correctable in PS or PTLens. Distortion is what you'd expect, barrel at wide, pincushin at long - again PTlens does an incredible job at correcting. Let's all remeber that this is the digital age. Minor issues are very easily correctable. That's why the RAW format was introduced. The only thing that bothers me with this lens has nothing to do with images, but the focus speed and noise. Yes, I've been spoiled by Nikon's AF-S. On this lens, focus is slow and noisy. Keep in mind, I'll stick with my own advice. I'm comparing the focus to a much more superior and read more expensive focus system. All in all, a very good value for the money.

Similar Products Used:

Nikon 18-70, AF 80-200 2.8, 50 1.8

Light weight
Compact
Very good value for money
Very sharp to about 50mm
Chromatic aberrations is OK

vignetting could be better when lens is fully open
Could be sharper above 50mm
need to keep an eye on auto focus, sometimes misses
little soft at the far edges

I have used this lens for 6 month now and brought it on the the basis of a low weight option when traveling and using 350D. This lens to work extremely well out side and in well light areas. Compared to my 16-35mm Canon in most situations it is difficult to see the difference in image quality. The 16-35mm has slightly more contrast in difficult situations and the focus is more reliable. This is not to say that the focus is bad in the Sigma. Comparing the resolution, I can’t tell the difference between two. The Sigma is very sharp until about 50mm and then fall off a bit. Again this is only noticeable in large prints. I find difficult to understand the criticism of this lens when it costs nearly 10 time less than my Canon 16-35mm. Maybe I am not as intolerant as some. Yes, the focusing motor does make more noise, but is not objectionable. The focus is slower, but this hasn’t been a problem. The speed is slower which is a problem for me when making inside shots without a flash. The built is no where as nice as the Canon but the Sigma light and compact. And 2mm at the bottom end does make a difference which I miss. I don’t know if I got an exceptional good copy, but one thing I learnt very early on when buying lenses, check them out thoroughly in the shop before handing over any cash. In particular check that the lens focuses to infinity.

Customer Service

non required as yet

Similar Products Used:

Canon 16-35mm f/2.8L
Sigma 30mm f/1.4
Canon 50mm f/1.4
Canon 85mm f/1.8
Canon 28-70mm f/2.8L

Range

Slow and suspect autofocus

Should be a great walkabout lens with ideal range on Canon 300D, but unfortrunately find it to be incredibly inconsistent as far as focus goes - far too many 'not quite focussed' shots unless in really good light. Overall I am a Sigma fan with both the 100-300 F4 and 70-300 APO previously delivering above expectations but this one is a disappointment....

Similar Products Used:

Canon 18 - 55, Canon 50 1.8 Mk 1

Versatile focal length. Light weight.

Soft soft soft. CA and distortion at both ends. Drab colors and poor contrast.

Bought this lens in Seattle for a walkaround lens for a vacation trip to that city. I returned it after two days---it was simply way too soft, much too slow and too slow to focus. Pay the extra money and get the Sigma 24-70 f2.8 or the Sigma 18-50 f2.8---or both. Don't waste your money on this lens.

Customer Service

NA

Similar Products Used:

Canon 18-55 Canon 28-105

Flexible zoom range Sharp images Build Quality Size ideal for travelling and casual shooting Bang for the buck

None so far

I was looking for a general purpose lens that had an extra zoom range, sharp on all focal lengths, easy to carry around, and most of all within my budget. I was not satisfied with the 18-55mm kit lens that came with my Canon 300D. The images were soft and build quality was rather so-so. I did my homework and decided on this Sigma 18-125mm DC. Bought it from a local distributor, took close to a hundred shots with it. Bottomline, I was IMPRESSED. I recently took it to a company outing down south, and out of the 70 plus shots taken, only 5 came out soft. But that's just me making a mess of things :-) Very decent and valuable. I boxed up my 18-55mm kit lens. The Sigma stays on my Rebel 90% of the time. I do have a 50mm 1.8, another valuable lens, for portraits and night shots. But that's another story. I'd recommend the 18-125mm to those who are looking for an alternative or replacement to their kit lens. Nice zoom, sharp images, easy on the wallet.

Customer Service

None so far

Similar Products Used:

EF-S 18-55mm EF 50mm 1.8 II

Quality and price. Light weight. Zoom range replaced two lenses.

None really

Purchased this item due to zoom range. Very impressed with sharpnes of images and color. Zoom motor a little slow and a little nosiy, but this does not detract from the overall quality of the lens. After using it a few times I sold my Canon 28/135 IS and my Tamron 19/35 lenses as this lens is produces superior images.

Customer Service

Not used.

Similar Products Used:

As mentioned in product review.