Best travel superzoom lenses explained
When travelling, some photographers choose to leave the DSLR at home and make do with a compact camera. But taking your DSLR doesn't mean getting bogged down with loads of kit. Whether you're on the beach, hiking in the hills or getting acquainted with local culture, your trusty DSLR and a single lens is often all you need for top-quality creative shots. Especially if the lens happens to be a superzoom.
As well as cutting out the extra weight, excess baggage and general inconvenience of carrying around multiple lenses, a superzoom lens has another key advantage for holiday shooting.
Picture yourself standing on a sandy beach with a fresh sea breeze blowing in off the ocean. You want to switch to a telephoto lens to capture some surfing action, only to suffer the instant panic of wondering how much of the sand blowing around will end up dumped on your camera's sensor. With a superzoom, all you need is a quick flick of the wrist and you're ready to start shooting.
Even in the cleanest, most dust-free environments, superzoom lenses still have the edge when it comes to reacting to surprising situations. With the capability to switch instantly from a wide angle to a telephoto focal length, and anything in between, you're ready for any photo opportunity that presents itself suddenly.
You can be shooting a wide-angle landscape one second, then zooming in for a close-up of passing wildlife the next.
But if superzooms are so great, what's the point of limiting yourself to a prime lens, or a lens with a more modest zoom range? Inevitably, a massive zoom range comes with compromise.
First off, prime lenses tend to be faster, with a bigger maximum aperture. This is great for blurring the background with a small depth of field, as well as for avoiding camera shake at fast shutter speeds.
That said, superzoom lenses enable a fairly shallow depth of field at their smaller maximum apertures if you shoot at the longer end of the zoom range. Many superzoom lenses also have built-in optical stabilisation, which typically gives a four-stop advantage in fending off camera shake.
Olympus, Pentax and Sony superzooms lack optical stabilisation, but current camera bodies from these manufacturers generally have effective sensor-shift stabilisation instead. Sure, any amount of stabilisation can't counteract movement on the part of the subject being photographed, but then again, the latest DSLRs maintain very good image quality at fairly high ISO settings, so you can still get fast shutter speeds when you need them.
Compared with a basic prime lens, a superzoom will often have around three times as many elements built into a complex array of groups that move back and forth to enable an extremely large zoom range.
Ultimately, the trade-off for the extra convenience is a loss in image quality. Most zoom lenses suffer from noticeable barrel distortion at the wide-angle end and pincushion distortion at the telephoto end.
With superzoom lenses, these distortions can be more pronounced, but some camera bodies have options for making automatic corrections at the shooting stage. Otherwise, you can apply distortion correction in Photoshop when editing your images.
Chromatic aberration, also called colour fringing, tends to be more prominent in superzoom lenses. These fringes are usually most noticeable around high-contrast lines, such as tree branches shot against the sky, and towards the edges and corners of the frame.
Again, though, current Nikon and Pentax cameras can apply corrections automatically while shooting. Otherwise, it's another job for Photoshop. Raw-processing programs are usually effective at correcting chromatic aberrations, but given the often large data sizes of raw files, many of us prefer to shoot in JPEG mode for holiday snaps.
Autofocus tends to be acceptable in superzoom lenses, although it's usually based on comparatively humble standard motors rather than upmarket ultrasonic ones. The exceptions in this group are the Nikon AF-S DX 18-200mm f/3.5-5.6G ED VR II, Sigma 18-250mm f/3.5-6.3 DC OS HSM and Tamron AF 18-270mm f/3.5-6.3 Di II VC PZD lenses.
Of these, the Sigma and Tamron optics have small ultrasonic motors which, while fairly quiet, aren't any quicker than conventional alternatives. It's only the Nikon 18-200mm that boasts the more advanced ring-type variant of ultrasonic autofocus, which is fast and features full-time manual focus override.
So, let's take a closer look at eight superzoom lenses and what they have to offer.
Canon EF-S 18-200mm f/3.5-5.6 IS
Canon EF-S 18-200mm f/3.5-5.6 IS - £415
Like Canon's budget kit lenses, this 18-200mm optic lacks the finery of USM (ultrasonic motor) autofocus or even a focus-distance scale on the barrel. Unlike the cheap 18-55mm IS kit lens, however, the 18-200mm features a metal rather than plastic mounting plate. More good news is that the four-stop image stabiliser features auto detection for both panning and tripod use.
The Canon is quite bulky, the biggest lens in the group, just ahead of the Sigma 18-250mm. It's about 35g lighter than the Sigma, but it lacks a lens hood, which will set you back another £50 for the EW-78D petal-shaped model, although third-party versions are available online for much less.
The zoom ring is large and has a very smooth, easy-twisting action. The downside is that zoom creep was appalling in our review sample – the zooming mechanism went into free-fall if the lens was pointed upwards or downwards. This is disastrous for tripod-mounted shooting, but at least there's a zoom lock switch for carrying the lens around safely.
Sharpness is adequate rather than particularly impressive, but it remains fairly consistent throughout the zoom range. The Canon is pretty average in terms of colour fringing and distortion, but if you're shooting in raw mode corrections are fairly easy to apply in the Digital Photo Professional program that Canon supplies with all of its DSLRs.
Sharpness test
Sharpness across the focal range is consistently good at the centre, but as the focal length is increased the edge sharpness drops.
Fringing test
At the mid-point of the focal range, there are mild signs of fringing at the centre. Throughout the rest of the focal range, fringing is minimal.
Distortion test
At 18mm, the Canon suffers from one of the heaviest barrel distortion results. At the middle and longest focal lengths, distortion is average.
Image test verdict
Sharpness is generally good and fringing is minimal throughout the focal range. At 18mm, barrel distortion is very much apparent.
Score: 3/5
Nikon AF-S DX 18-200mm f/3.5-5.6G ED VR II
Nikon AF-S DX 18-200mm f/3.5-5.6G ED VR I I- £590
You can't help but feel that many superzoom lenses are built down to a price, but the Nikon 18-200mm seems a real quality item. Stand-out features compared with all the other lenses on test include ring-type Silent Wave ultrasonic autofocus, which is rapid and accurate, as well as full-time manual override. It's also the only lens to include a distance scale that's neatly positioned below a viewing window, and overall build quality feels well above average.
Nikon's latest-generation vibration reduction lives up to its four-stop promise, edging ahead of the system fitted to the original version of this lens. The dual-mode stabiliser includes both normal and active modes, toggled by a switch on the lens barrel. The lens also suffers slightly less zoom creep, although it's still a bit of an issue in the 24-135mm focal range. At least the new edition includes a zoom lock.
The focus ring is towards the rear of the lens barrel, but because it doesn't rotate during autofocus, this doesn't impair the excellent handling. The focus and zoom rings are smooth and precise and the optical quality is extremely good, with excellent sharpness through most of the range.
Distortions are pronounced at the wide-angle and telephoto ends of the zoom range and colour fringing can be noticeable at the edges of the frame. However, in-camera corrections for distortion and chromatic aberration work well in Nikon's current bodies.
Sharpness test
Sharpness at the widest and middle focal lengths is excellent, but it drops at 200mm. It falls towards the edges at all focal lengths.
Fringing test
Fringing is consistently low, showing little to no signs across the frame. At 200mm, there's a mild green fringe towards the edges.
Distortion test
Distortion at 18mm is heavy and only a fraction less than the Sony. At the middle and longest focal lengths, pinch distortion is average.
Image test verdict
Sharpness at all focal lengths is good and beaten only by the Sony. Fringing across the frame is minimal, but barrel distortion at 18mm is high.
Score: 5/5
Olympus Zuiko Digital ED 18-180mm 1:3.5-6.3
Olympus Zuiko Digital ED 18-180mm 1:3.5-6.3 - £430
The focal range of Olympus's superzoom looks pretty standard fare at 18-180mm, but that's before you take the Four Thirds factor into account. With a 2x focal length multiplier, the lens has an effective zoom range of 36-360mm, which will leave many photographers wanting at the wide-angle end.
On the plus side, the Olympus optic is compact and lightweight, which is ideal for a travel lens. It also feels well built, and there's practically no zoom creep. Autofocus is a little loud and shrill, but the focus ring doesn't rotate when doing so. Better still, the focus ring's electronic coupling enables very precise manual focus, which is also available as a full-time override in autofocus mode.
Coupling an effective 360mm telephoto range with a f/6.3 aperture, the lens pushes the boundaries of sensor-shift stabilisation in Olympus bodies. Camera shake was more of a problem than with the latest optical stabilisers fitted to Canon, Nikon, Sigma and Tamron lenses, and we got an advantage of between two and three stops.
Sharpness is excellent in the centre of the frame and well above average towards the edges and corners, although there's an alarming drop-off in clarity at the long end of the zoom range. Distortions are fairly well controlled, although colour fringing is very noticeable outside the central area of the frame.
Sharpness test
At the widest and middle focal lengths, the Olympus produces good results, which drop at 180mm. Sharpness falls towards the edges.
Fringing test
Centre fringing at the middle focal length is the best in test. At 18mm, a red fringe (and at 180mm, a green fringe) shows towards the edges.
Distortion test
Barrel distortion at 18mm is worse than expected, especially because the Four Thirds sensor increases the effective focal length to 36mm.
Image test verdict
Sharpness is generally good throughout the focal range, with a drop at 180mm. Fringing and distortion are average compared to others on test.
Score: 3/5
Pentax smc DA 18-135mm f/3.5-5.6 ED AL [IF] DC WR
Pentax smc DA 18-135mm f/3.5-5.6 ED AL [IF] DC WR - £530
relative newcomer to the superzoom market, the Pentax 18-135mm is the smallest and lightest in the group. Naturally, downsizing is helped by the fact that it has a modest zoom range. Even so, the effective focal range of 27-202mm gives plenty of versatility when shooting.
In our tests, the Pentax optic was a joy to use with its oversized, silky-smooth zoom ring. It suffered no zoom creep, which is just as well because the lens doesn't feature a zoom lock. The built-in autofocus motor is extremely quiet, and comes complete with full-time manual override – Pentax calls it a 'Quick-Shift' focus system. Our only reservation is that a larger focus ring would be easier to use.
Considering the lens's relatively modest zoom range, we'd expect less compromise in terms of the optical quality. Sure enough, centre sharpness is exemplary throughout the entire zoom range, but sharpness drops off disappointingly at the edges of the frame, especially at longer focal lengths.
Colour fringing towards the corners of the frame is among the worst of any lens on test, and distortion is also poor, especially at the longer end of the zoom range. On the plus side, all current Pentax DSLR bodies have built-in automatic correction for colour fringing and distortion. Even so, we'd expect better optical quality considering the relatively short zoom range and the high price.
Sharpness test
Centre sharpness at all focal lengths is excellent. However, as with other lenses in the test, the sharpness drops towards the edges.
Fringing test
Fringing at the centre is low at all focal lengths, but at the widest end of the range there are signs of blue fringing, and at the longest, green.
Distortion test
Distortion at the widest focal length is average, and easily correctable at the middle and longest. Pinch distortion is higher than average.
Image test verdict
The Pentax resolves good centre sharpness across the focal range. Fringing at the extremes of the focal range is noticeable at the edges.
Score: 3/5
Sigma 18-200mm f/3.5-6.3 DC OS
Sigma 18-200mm f/3.5-6.3 DC OS - £290
Sigma's 18-200mm lens is bigger and heavier than some lenses with a mightier zoom range, including the Sony 18-250mm and Tamron 18-270mm. Indeed, it has almost exactly the same dimensions as the Sigma 18-250mm. When you're looking for a lens that's compact and lightweight for travel, yet delivers a generous zoom range, the Sigma 18-200mm is disadvantaged immediately.
The maximum aperture of f/6.3 is also a bit disappointing, being half a stop slower than the Canon and Nikon 18-200mm lenses. At least lenses that offer focal lengths up to 250mm or 270mm have a more compelling reason for the extra half stop. It also lacks the quiet HSM autofocus system found in Sigma's newer 18-250mm option. The standard micro motor in this lens is quite shrill and noisy.
Optical stabilisation is below par compared with other stabilised lenses in the group, because as one of Sigma's first stabilised lenses to hit the market, the 18-200mm features an old-generation system. In our tests, it gave an advantage of only between two and three stops.
The build quality feels pretty high, but the zoom ring goes through a nasty stiff patch in the middle of its travel. However, there's practically no zoom creep, and the lens also features a zoom lock. Optical quality for sharpness, lack of colour fringing and distortion proved average across the board.
Sharpness test
Centre sharpness across the range is good, just beating the Sigma 18-250mm, but there's a steep fall-off towards the edges.
Fringing test
There's a slight red fringe towards the edges at 18mm, and green at 200mm. However, the effect of fringing overall is minimal.
Distortion test
The influence of barrel and pinch distortion are more pronounced than on the 18-250mm, but results show an average score.
Image test verdict
Centre sharpness is not far behind the 18-250mm. It copes well with distortion and fringing, but edge sharpness suffers at all focal lengths.
Score: 3/5
Sigma 18-250mm f/3.5-6.3 DC OS HSM
Sigma 18-250mm f/3.5-6.3 DC OS HSM - £400
Not quite identical twins, the Sigma 18-250mm has almost exactly the same dimensions and the same 72mm filter thread, zoom lock and general finish as the Sigma 18-200mm f/3.5-6.3 DC OS. There are some important differences, however, apart from the extra 50mm length at the telephoto end. For starters, the 18-200mm is available only in Canon, Nikon and Sigma mount options, whereas the 18-250mm adds Pentax and Sony options to the list.
The 18-250mm also has a quieter HSM autofocus system, although it's only the basic version, which isn't particularly fast and doesn't have manual focus override. This also means that the focus ring rotates during autofocus, but it's smaller and further away, at the front end of the lens barrel, so there's less chance of your fingers fouling its action.
The 18-250mm lens features Sigma's latest-generation optical stabiliser, which gave between three and four stops of anti-shake benefit in our tests. It was almost as good as the Canon, Nikon and Tamron lenses, which all gave a slightly more consistent four-stop advantage.
Distortion is quite well controlled, which is impressive considering the extra-large zoom range. Sharpness is less so, being mediocre at 18mm and going downhill all the way to 250mm. Colour fringing is quite pronounced towards the edges of the frame, particularly at the shortest and longest focal lengths.
Sharpness test
Centre sharpness across the focal range is good compared with the other Canon-fit lenses, but it drops off steeply towards the edges.
Fringing test
Fringing across the frame at all focal lengths is minimal, but at 18mm there's some mild blue fringing towards the edges.
Distortion test
The Sigma lens has less barrel distortion at 18mm than all the other lenses on test and is very easy to correct.
Image test verdict
The Sigma 18-250mm has the least barrel distortion in the test and only minimal fringing. Sharpness is good, but it does suffer towards the edges.
Score: 3/5
Sony DT 18-250mm f/3.5-6.3
Sony DT 18-250mm f/3.5-6.3 - £470
Noticeably smaller and nearly 200g lighter than the Sigma equivalent, the Sony 18-250mm lens makes a compact travelling companion. Part of the weight saving is due to the absence of an optical stabiliser, because it relies on sensor-shift stabilisation in Sony bodies.
Like the Olympus 18-180mm lens, the anti-shake performance didn't quite match optical stabilisation, giving between two and three stops of benefit. Considering the maximum aperture is f/6.3 at the longest equivalent focal length of 375mm, you'll find yourself frequently reaching for the camera's ISO button for faster shutter speeds.
There's little in the way of advanced features, although you at least get a basic distance-scale printed on the focus ring, and there's a zoom lock. The latter is hardly necessary because the lens is remarkably free of zoom creep.
Optical quality is a mixed bag. The Sony lens is sharp at the centre of the frame throughout its whole zoom range, but edge sharpness is disappointing. Colour fringing at the edges of the frame is very well controlled for an 18-250mm lens, at least from the wide end of the focal range up to 200mm. Fringing only becomes really noticeable beyond this point. Distortion was more of a problem, with extreme barrel distortion at the wide-angle end.
Considering the price, and the lack of an optical stabiliser or ultrasonic autofocus, we'd expect the Sony to deliver a bit more.
Sharpness test
Centre sharpness at all focal lengths is excellent, but it falls sharply towards the edge at the middle and longest focal lengths.
Fringing test
At the centre of the frame, fringing is minimal, but there's blue fringing at the frame edges at the extreme ends of the focal range.
Distortion test
Barrel distortion at 18mm is the highest in the test. At other focal lengths, it drops and changes to pinch distortion at the long end.
Image test verdict
The Sony produces the best results for centre sharpness. However, it drops dramatically towards the edges. Distortion at 18mm is also very high.
Score: 3/5
Tamron AF 18-270mm f/3.5-6.3 Di II VC PZD
Tamron AF 18-270mm f/3.5-6.3 Di II VC PZD - £495
This isn't Tamron's old 18-270mm with a PZD (Piezo Drive) autofocus motor fitted – this is a whole new lens. Optically, it's based on 16 rather than 18 elements, although they're still arranged in 13 groups. The vibration correction system has been revised, and while it proved good for a four-stop advantage, it's much smaller and lighter than the older system.
This is one of the factors that makes the 18-270mm much more compact than its predecessor, and little more than two thirds of the weight. The filter thread has also been reduced, from 72mm to 62mm. The PZD autofocus is a lot quieter than the standard micro motor fitted to Tamron's older 18-270mm lens. But because it isn't a ring-type ultrasonic system, it's still not particularly fast and it lacks full-time manual focus override.
Build quality is a step up from the older Tamron, and the jerky zoom ring has been updated with a low-friction replacement. However, zoom creep is a real problem. It shouldn't be an issue for handheld shooting, but it's a nightmare on a tripod. At least there's a zoom lock for safe carriage.
Sharpness is good and consistent throughout the zoom range, although the maximum aperture of f/3.5 is best avoided at the wide-angle end. Colour fringing is negligible at the centre of the frame, but poor around the edges, especially at each end of the range. Pincushion distortion is above average at medium focal lengths.
Sharpness test
Centre sharpness at all focal lengths is good. The quality drops at the edges, but not as dramatically as on the Sigma lenses.
Fringing test
Green fringing at 18mm and 270mm is apparent. There's little sign of any colour fringing at the mid-point of the focal range.
Distortion test
Distortion at all lengths is average. At 18mm, barrel distortion is apparent, and pinch distortion is quite high at the mid-point.
Image test verdict
The Tamron has good centre sharpness at all focal lengths, and although there's a drop towards the edges, it's lower than most of the other lenses.
Score: 4/5
Benchmarks
The Sony lens acheived a high score for centre sharpness, followed by the Pentax optic. The Nikon and Olympus lenses did well at their widest and middle focal lengths, but drop at 200mm and 180mm respectively.
The Olympus lens has good edge sharpness at the mid-point of the focal range, but results for the widest and longest focal lengths were more average.
The tests reveal interesting relationships between lenses and manufacturers. The Canon EOS 7D produces softer details in its JPEG images compared with the Nikon, Olympus, Sony and Pentax camera bodies.
At 18mm, all lenses show barrel distortion, changing to pinch distortion at the mid-point of the focal range. All lenses showed increased pinch distortion at the mid-point.
All but the Canon, Nikon and Sigma 18-200mm lens showed heavy fringing at the edges at the longest focal length.
The Nikon comes out on top for its consistency.
Verdict: Best travel superzoom
Pick up a Nikon 18-200mm lens and everything just feels right. It's a brilliant blend of compact, lightweight-yet-sturdy build, natural handling, and high-tech extras, most notable of which are the distance scale, neatly mounted beneath a viewing window, and a fast, ring-type ultrasonic autofocus complete with full-time manual override. Most importantly, the image quality is simply excellent for a superzoom lens.
For our money, it comes closer than anything else on the market to genuinely replacing a good quality standard zoom and telephoto zoom in a single, convenient lens.
In comparison to the Nikon lens, Canon's 18-200mm option is a bit poor, although it's much cheaper. The Olympus 18-180mm offers reasonable value, but the 2x focal length multiplier of the Four Thirds system means it loses out in wide-angle coverage.
At the other end of the scale, Pentax's new 18-135mm lacks telephoto reach. The Sony 18-250mm fares much better in terms of zoom range, but feels a little basic considering its high price. Of the two Sigma lenses, the 18-250mm is more refined, with its later-generation, better performing optical stabiliser and hypersonic autofocus.
However, even the upmarket Sigma has been outclassed by Tamron's 18-270mm PZD lens. This is available in Canon, Nikon and Sony mount options, although the Sony edition lacks Tamron's excellent vibration correction system.
At 450g the Tamron is far lighter than both Sigma lenses, with the 18-200mm weighing in at 610g and the 18-250mm at 630g. In fact, only the Sony and Pentax are lighter, making the Tamron lens an attractive choice to take on holiday.
However, overall we think the Nikon AF-S DX 18-200mm f/3.5-5.6G ED VR II is the best travel superzoom lens.
Best for Canon APS-C format users:
Tamron AF 18-270mm f/3.5-6.3 DI II VC PZD
What's good: Compact, with quiet autofocus.
What's bad: Could be a little sharper at the telephoto end, and colour fringing is noticeable.
Our verdict: good build and handling in a surprisingly small and lightweight package.
Best for Pentax users:
Pentax SMC DA 18-135mm f/3.5-5.6 ED AL [IF] DC WR
What's good: Brilliantly small and lightweight.
What's bad: modest focal range.
Our verdict: Considering the automatic correction of distortion and fringing in Pentax SLRs, it's a good buy.
Best for Nikon DX users:
NIkon AF-S DX 18-200mm f/3.5-5.6G ED VR II
What's good: Advanced silent Wave autofocus, great build quality and optics.
What's bad: Zoom range is a little modest.
Our verdict: for nikon owners, this is by far the best choice of superzoom.
Best for Olympus users:
Olympus 18-180mm 1:3.5-6.3
What's good: excellent edge-to-edge sharpness throughout most of the zoom range.
What's bad: Lack of wide-angle coverage.
Our verdict: overall optical quality lags behind most of the ZuIko dIgital range.
Best for Sony users:
Sony DT 18-250mm f/3.5-6.3
What's good: mighty zoom range and excellent sharpness at the centre of the frame.
What's bad: expensive, sharpness drops off.
Our verdict: the sony's not great value, but it's compact and image quality is impressive
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