Review Sigma 18-200mm Contemporary
The Sigma 18-200 mm Contemporary is smaller, lighter and cheaper than its classmates, like, for example, the Canon 18-200 mm. Also in comparison to similar superzooms that we have tested so far, Sigma 18-250 mm, Tamron 18-270 mm and the Nikon 18-200 mm, the Sigma 18-200 mm C wins in terms of compactness, weight and list price. These are important considerations for the target group, amateur photographers who want to have a not-too-expensive, all-round lens with a hefty zoom range, to be able to head out without having to lug a lot of weight along and without having to change lenses. We previously published our first, very positive, experiences with the Sigma 18-200 mm. Now we had the opportunity to test this lens more comprehensively. How good is the optical performance of the first superzoom in the Sigma Contemporary series?
Sigma 18-200mm F3.5-6.3 Contemporary @ Canon 650D
|With more than 10 times zoom range, you bring a subject quite close to you, but you can also create a landscape shot without changing lenses. At this zoom range, you practically always have enough. To illustrate, you see above two shots: taken right after each other from the same position, first at a focal length of 18 mm, then at a focal length of 200 mm.|
Construction and auto focus
First of all, you notice how compact this zoom lens is. Shorter (16%), narrower (10%) and lighter (30%) than the Canon 18-200 mm. In comparison to the Canon 18-55 mm STM kit lens, the Sigma 18-200 mm C is only 2.5 cm longer and 1 cm wider, while the zoom range is 3.5x as great. The Sigma 18-200 mm's housing is made of a light and sturdy composite material; the mount is metal. Like all superzooms, this lens is more than twice as long when you set the longest focal length and use the included lens hood. On the lens are three sliding switches: for AF vs. manual focus, on/off for image stabilization and to block the zoom during transport.
The zoom ring turns smoothly. Perhaps even a little too smoothly. When you have the camera hanging around your neck without locking the lens, the zoom shifts on its own from 50 mm to 80 mm ("creeping"). The focus ring has a relatively short run, so you can quickly set focus manually, but it is also more difficult to accurately to focus manually. Because superzooms have no large aperture, that's not terrible. The Hyper Sonic Motor (HSM) ensures fast, silent AF. Many cameras focus less quickly and less accurately at the longest focal length of a super zoom, because the image is then darker and has less contrast. In this test, we have therefore paid some extra attention to the operation of the AF at the longest focal length. That's much better than expected: the accuracy is good and the AF speed in nice weather was amazingly good.
It's nice that the Sigma 18-200 mm is equipped with built-in image stabilization. Built-in image stabilization ('OS') ensures that you can keep shooting longer by hand, without you having to set higher ISO values on the camera to prevent motion blurred images.
We have tested the image stabilization at a focal length of 46 mm. If you shoot by hand, then the resolution begins to fall off from 1/50 second. Pictures made with image stabilization, but at a shutter speed of 1/13 second, it appeared to be sharper. The built-in image stabilization yielded a gain of 2 to 3 stops.
Vignetting Sigma 18-200mm Contemporary
Vignetting is – as with the Canon 18-200 mm zoom lens –kept well in check for a zoom lens with such a large zoom range. At maximum aperture, vignetting in some situations will be visible, but if you have used a smaller aperture, whereby the sharpness also increases, then you will not suffer from vignetting. The picture here is made at maximum aperture.
Both the test camera and the Sigma 18-200 mm C are not designed for action photography. However, our results, made at the longest focal length and at maximum aperture, were much, much better than expected. Under these types of conditions, you don't expect to come home with 100% successful shots, if only because I'm no action photographer. The number of successful shots was as high as in an earlier session, when I photographed winter sports with a 70-200 mm f/2.8 lens, which is about 5 times as expensive as the Sigma 18-200 mm. A more expensive, bright lens gives sharper pictures with a nicer bokeh. And you pay heftily for that.
The course of the distortion is typical for a superzoom and goes from visible barrel-shaped at 18 mm, to pincushion-shaped at focal lengths above 30 mm. In particular, the barrel distortion at the shortest focal length is every now and then clearly visible. A beautiful part of the design, is that this distortion is no longer visible at 22 mm.
Distortion is easy to correct automatically for RAW files in Lightroom or Photoshop with lens correction profiles. And if you don't have the access to these programs: because the distortion between 28 mm and 200 mm is so constant, you can apply the same correction for that entire zoom range.
Even under the most extreme conditions, you have remarkably few ghosts or flaring. The picture here is made straight into the Sun. The flared area around the Sun is extremely small and there are – despite the very bright light source – no ghosts due to internal reflections. This is just, regardless of the price of a lens, really very good.
Sharpness: zoom or megazoom?
Some people expect from a mega zoom the same image quality as from much more expensive lenses with a fixed focus or of much more expensive, bright zoom lenses. That is not realistic. The current megazooms deliver acceptable image quality over the entire zoom range, which is better than what you get with a compact camera. At most focal lengths, the highest sharpness is reached after stopping down 1 stop. The sharpness in the center is always somewhat higher than in the outer corners. Even at the longest focal length, which used to be the weakness of a megazoom, the picture is still usable. To give you an impression of the sharpness at the longest focal length, you can enlarge a couple of the test shots on this page up to 100%. For those who attach a great importance to sharpness, the bright Sigma 17-70 mm C is an affordable alternative.
Sigma 18-200 mm C @ 200mm, 400 ISO, 1/4000 sec, f/6.3 (detail)
Chromatic aberration Sigma 18-200mm Contemporary
|With lateral chromatic aberration, in the corners of the picture not all colors land in exactly the same place, meaning that in the corners at sharp contrast transitions, you find green and purple edges. Also the sharpness in the outer corners drops a bit. If you compare your pictures made with the Sigma 18-200 mm C with the Canon 18-200 mm, without applying lens corrections (for chromatic aberration and vignetting; see the RAW table below for this test), then both lenses at both the shortest and the longest focal lengths are evenly matched in terms of chromatic aberration and sharpness. At a focal length of 200 mm, the chromatic aberration was more noticeable in the test shot made with the more expensive Canon 18-200 mm than with the Sigma 18-200 mm C. Below you can see a partial enlargement from a corner of the image.
||Above you can see a 100% partial enlargement, made from an outer corner of a test shot, in which you can recognize chromatic aberration. This is the worst case we found. Even if you don't correct for chromatic aberration, the chromatic aberration in this worst case is only noticeable if you print larger than A4 size. With Nikon cameras, all jpg files are automatically corrected for chromatic aberration, but on a Canon camera you can only correct Canon lenses for chromatic aberration. Therefore, the Canon 18-200 mm for jpg files that are listed in the table at the conclusion scores slightly higher for chromatic aberration and sharpness than the Sigma 18-200 mm C. If you correct your pictures made with the Sigma 18-200 mm C afterwards for chromatic aberration, then these differences diminish.
The Sigma 18-200 mm Contemporary is also ideal for close-up photography. And that makes the lens extra versatile. The closest focusing distance is only 39 cm, which gives an image scale of 1:0.33. That is better than the 0.26 x that the previous version of the Sigma 18-200 mm managed. And Sigma let that be reflected by adding "macro" to the already not so short: Sigma 18-200 mm F3.5-6.3 DC Macro OS HSM C. It isn't real macro, which we pin to the definition that the image on the sensor is the same size as the original (image scale 1:1).
All superzooms have a less woolly background blur. And the Sigma 18-100 mm C is no exception, as you can see in the practice shots, made in the snow. However, we were quite pleased – for a super zoom – by the shot from our bokeh test setup, created at the longest focal length. But if you really want a nice bokeh, without spending too much money, then choose a bright lens with a fixed focal length or the Sigma 18-70 mm f/2.8-4 C.
Conclusion Sigma 18-200mm Contemporary test with Canon 650D