Sigma 18-50mm f/2.8 EX DC
(From Sigma lens literature) This lens offers a large aperture of f/2.8 over its entire range of focal lengths and its large depth of field offers greater freedom of creative expression.
This lens is perfectly suited for low light conditions indoors or at dusk. It covers wide angle to medium telephoto and is ideally suited to a wide range of subjects. It is an ideal large aperture standard zoom lens for digital SLR cameras featuring APS-C size image sensor.
The characteristics of digital SLR cameras were taken into consideration when designing the lens power layout. A Special Low Dispersion (SLD) glass lens element provides effective compensation for lateral chromatic aberration, which is likely to occur with digital SLR cameras. The use of two aspherical lens elements provides correction for various aberrations and makes high quality images a reality throughout the entire zoom range.
A Special Low Dispersion (SLD) lens and two aspherical lens elements provide excellent correction for all types of aberrations. The design produces a compact and lightweight, yet robust, construction with an overall length of 84.1mm (3.3 in.) and maximum diameter of 74.1mm (2.9 in.) and weight of 445g (15.7 oz).
Super Multi Layer (SML) coating gives the best color balance and reduces flare and ghosting from which digital cameras tend to suffer.
This lens has a minimum focusing distance of 28cm (11 in.) throughout the entire zoom range which is very convenient for close-up photography.
The lens is equipped with an inner focusing system. The non-rotating front lens element makes the lens suitable for using its petal-type lens hood and circular polarizing filters.
This lens has excellent correction for vignetting which is a common problem of large aperture lenses. Its new design ensures superior peripheral brightness.
An updated version of this lens improves macro capability.
Sigma 18-50mm f/2.8 EX DC
Sigma 18-50mm f/2.8 EX DC User Reviews
9 out of 10 points and recommended by Nikoboyd (12 reviews)Excellent IQ; very very sharp from edge to edge from f/4 to f/11, solid built, very light weightnothing
Firstly, I bought the macro version "used" and have problems with the communication between the lens and my S5Pro, so, I returned the lens and I bought this old stock non macro version.reviewed December 4th, 2009 (purchased for $360)
I have an experience that any zoom lenses usually sharp at 18mm. So,I zoomed the lens at 50 mm. tried the lens with every f/ and see what this thing can do.
At 2.8, sharp at center and SLIGHTLY soft at very far corner.
It's extremely sharp from edge to edge from f/4 to f/11. So sharp that can compete with my vintage 50 1.8 AIS. Yes, it's that sharp.
But from f/16, IQ drops because of diffraction.
About the construction, it's very solid. I prefer this lens to Nikkor 17-55 because of it's very light weight.
Very good lens, highly recommend.
9 out of 10 points and recommended by f43tgv (16 reviews)Sharp, CheapMock teflon finish
I bought this lens from my local camera store to go with an EOS 20D, having decided to go back to Canon. I always buy seconhand, the savings are huge.reviewed November 16th, 2007 (purchased for $427)
I have used the 17-40L Canon lens a lot in the past, and have always thought it is a great lens.Very pricey though, not a lens I would stump up for at new prices.
At first glance I was not over impressed with the Sigma, as new , in its box for less than half the cost of a new 17-40L.
I really dont like the Sigma finish on the EX Lenses, it is almost impossible to keep clean, its almost tacky.
However on the basis of "bring it back if you dont like it" I decided to give it a try.
A smart move. The lens is smaller and lighter than the Canon without feeling too flimsy. It has a sensible size and shaped hood too, unlike the bucket like affair the Canon comes with.
Having used the lens for a couple of hundred shots, I have to say I am mightily impressed.
The lens is very sharp indeed , the colour and contrast are excellent, and the edges are fine.
Clearly designed to work well with a cropped sensor, Sigma have got this lens right.
It balances beautifully on the Camera and works well with the built in flash, ie no shading.
I am happy with it, and having compared a number of shots I have taken with the 17-40L with the same or similar shots taken with this lens, can see no difference at all.
At half the cost, I cant argue.
A very, very good lens at a bargain price
8 out of 10 points and recommended by JGLarson (6 reviews)Extremely sharp, very compact, yet a wide max aperatureNo 17mm or even 16mm, No IS like the expensive Canon
As a Pro, this is the first lens that I purchased when I switched from Nikon/Fuji to the Canon system 1.5 years ago. I first got the Canon 20D, and thought this would be a great all purpose lens. And yes, it is. I wanted a general purpose wedding lens, that could focus in dim situations. This was before Canon came out with their 17-55 f/2.8 IS, but if I were buying today, I think I would have a tough time justifying the Canon lens that was 2x the price, poorer close focus range, ~50% heavier, and bigger, just to get Image Stabilization.reviewed January 13th, 2007 (purchased for $450)
I was originally going to couple it with a 100mm Canon Macro, and the Canon 70-200 f/2.8 IS to round out my begining kit. The 100 had focus accuracy issues, and had to be returned. But I found that the found that the range of the Sigma lens, it's close focus abilities, and it's resolution more than satisfactory. I have used it alot on location, but even used it for small studio catalog photography.
The resolution is very high at all apertures, and even good wide open. Sigma seems to have definately tweaked the optics to excell on a smaller chip camera, as I compared this to my friend's Canon 16-35mm f/2.8L series lens (full frame lens). The Sigma equalled or out-performed the L lens in resolution and flair control (for about 1/3 the price) in the entire zoom range (I have since also purchased a 17-40mm f/4L lens for my 5D, since my results with the 16-35 were so marginal).
Construction is not overly robust, but more than adequate, roughly equal to the Tamron 28-75 that I previously owned. The Tamron 17-50 lens was not out when I chose this lens, so I couldn't compare it at the time ( though I have been very pleased with 2 Tamron lenses when I owned Nikon/Fuji).
9 out of 10 points and recommended by Wolfini (10 reviews)IQ, size, weight, f2,8, priceAF-issues
This is my favourite walk-around lens for standard use, including landscape, cityscape, people, etc. (on a Canon 30d)reviewed January 5th, 2007 (purchased for $580)
IQ is really right up there with the big boys, and I can compare it to a 85/1,8 or a 200/2,8L.
Contrast is great, and I also like the colors although there is definitely a yellow cast. (Let´s call it "warm")
Sharpness is very good at 2,8 and gets even better when stopping down.
I also have to mention the very compact size and weight, which make it very useful to carry around all day long, which is really impressive for a constant f2,8 zoom.
So, the AF .... I consider myself lucky, as my specimen focuses fast and accurately - AT 50mm!
At WA settings the focus is more hit and miss (more miss then hit) - BUT: fortunately this lens is parfocal, which means, that focus is not changed by zooming. So I always focus at 50mm, and then zoom out to the appropriate setting. Yes, that is annoying sometimes, but the great IQ I get from such a small and light lens makes it worthwhile for me. (I should add that I have put AF on the *-key, so I do not have to refocus for every shot).
I also have an AF-issue when using the AF-illuminator of an external flash unit. Unfortunately my local Sigma service (Vienna) was not able to fix this, although I have read on the internet, that a solution for this specific issue exists. Pity. But I do not use flash very often anyway, and when I do I use other lenses.
Still: despite of its flaws I love the lens and even more so the pictures it produces, am very happy with it and will recommend it to anyone who asks me.
9 out of 10 points and recommended by kirehe (9 reviews)Relatively light, sharp, low distortion.Maybe you should buy the updated macro version instead
Sharp from f/4.0. Low distortion. Pretty good build quality. Rated as topclass in Sweden's premier photo magazin (and they're pretty stingy with that label).reviewed December 5th, 2006 (purchased for $370)
Only concern could be that perhaps it would be better to buy the Macro version - same lens but focuses closer.
9 out of 10 points and recommended by Magdy Kamel (3 reviews)light weight, wide coverage& sharp images
Enjoyable useage of this lens as the respionse for focusing is very reasonable. The image quality is also point of interests.reviewed June 27th, 2006
9 out of 10 points and recommended by gerrysnaps (5 reviews)Fast f/2.8 aperture and flexible zoom range in a small, durable packageNoisy and slower AF than with an AF-S lens
Sigma's 18-50mm f/2.8 EX DC is a wide, constant aperture autofocus zoom lens for use only with digital SLR cameras using APS-C sized sensors. The zoom range is ideal for covering events, going from wide enough to cover a scene or a table of guests, to a 'mild' telephoto good enough for portraits, so it is currently my most used lens. In the studio, it can find use for full-body portraits and groups, and its image quality holds up to scrutiny.reviewed May 2nd, 2006 (purchased for $450)
The Sigma 18-50/2.8 is an EX lens, which denotes high-quality construction. The lens feels solid and the weight is considerable for its size, making it feel packed, and it is, with fast glass. The special Sigma EX 'crinkle' finish is a love-it-or-hate-it look but has the advantage of being not easy to scratch. It has a 67mm filter thread. The lens mount is metal.
AF speed, since it does not have micromotors, is dependent on the camera body being used, but it is fast enough on a Nikon D50. AF action is unfortunately also noisy being without the benefit of Silent Wave Motor technology.
The lens focuses very close, closer than the Nikon 18-70mm (kit lens), but it is not a macro lens.
The Sigma is sharp through the zoom range, especially in the center area. The sharpness looks good at f/2.8 and excellent at f/4 and smaller. Light falloff shows up at the large apertures but is less noticeable past f/4.
I wrote a more complete review here: http://www.gadget-hack.com/2006/04/sigma-18-50mm-f28-ex-dc-af-lens-user.html
8 out of 10 points and recommended by rocketralph (3 reviews)Weightnone so far
Bought this as a replacement for the Canon 18-55mm "kit" lens. The comparison is like night and day. If I could do it all over again, I would have paid the extra $$ for the camera body only and this lens. Nice large focusing ring and the ability to use filters without them changing on you while it is focusing. The wider aperture is a bonus too.reviewed April 24th, 2006
9 out of 10 points and recommended by fstopjojo (8 reviews)18mm Wide (significant difference v. 28mm on 1.6x body), Great focal range, Fairly small and lightweight, Constant f2.8, Excellent center sharpness wide open, Minimum focusing distance nice, EX black finish, Price.Wide open edge performance average, Vignetting at 18mm wide open (somewhat expected though), CA wide open, No HSM/FTM, Not FF compatible.
This lens has a lot going for it (which I've stated in the "Pros" section above). A properly working copy delivers good sharpness and contrast even wide open. The focal range along with the constant f2.8 aperture makes it a serious alternative to the lovely 17-40L (at least on a crop body).reviewed November 3rd, 2005