Nikon 16.2 Megapixels D5100 DSLR Camera Review by GearGuide With Rating 4/5

Photography Quote of the Day - Susan Sontag - June 23

Comparing 3 SuperZoom Lenses - Canon 18-200 vs Sigma 18-250 vs Tamron 18-270

2011-06-23 12:41
Superzoom lenses are popular among amateur photographers as they are extremely versatile, and they allow photographers to take almost all kinds of photo with a single lens. In this article, we're going to compare the most popular SuperZoom lenses available in the market today, namely the Canon EF-S 18-200mm F3.5-5.6 IS, Sigma 18-250mm F3.6-6.3 DC OS HSM, and Tamron AF 18-270mm F/3.5-6.3 Di II VC PZD LD Aspherical (IF) MACRO lenses.

The Canon EF-S 18-200mm F3.5-5.6 IS

Announced on August 26 2008, the Canon EF-S 18-200mm f/3.5-5.6 IS SuperZoom lens can supports an focal length range equivalent to 29-320mm in the 35mm format. The lens features Canon's built in Optical Image Stabilization system which gives the equivalent effect of a shutter speed roughly 4 steps faster, for better image clarity, even in shaky shooting conditions. It also supports auto panning detection -- when you pan during a shot, it turns off the IS along either the horizontal or vertical axis, depending on camera orientation. With a minimum focusing distance of 45cm (17.7in) at all zoom settings, this lens should prove to be ideal for those situations where swapping lenses isn't an option. The lens is consisting of 16 elements in 12 groups and is made from environmentally friendly lead-free glass and contains UD glass and high-precision aspheric elements. Internal Focus (IF) mechanisms provide smooth focusing and make it easy to use angle-critical filters, such as polarisers and graduates. The lens comes with front and end caps but no lens hood; although an EW-78D lens hood is available as an optional accessory.  A gear-driven micro-motor system is used for autofocusing, instead of the USM ring-type motors found in many other Canon lenses, which are faster and more accurate. The lens also carries electronic contacts that provide information for E-TTL II flash metering. 

The Canon EF-S 18-200mm f/3.5-5.6 IS SuperZoom Lens is currently selling at around $599.95, via Here's the review summary by ePhotoZine, gave a rating of 3.5/5: "High zoom ratio lenses like this Canon optic are often a compromise regarding optical quality. For a lens of this type, the performance holds up very well. Shooting wide open at 18mm, sharpness in the centre of the image area already approaches very good levels, and clarity towards the edges of the frame is fairly good. Stopping down the aperture improves sharpness across the frame, peaking between f/5.6 and f/8, where sharpness in the centre is excellent and towards the edges it reaches very good levels. At 80mm, the good sharpness in the centre is maintained at maximum aperture, with sharpness towards the edges dropping to fair levels. Peak quality across the frame is again achieved between f/8 and f/11 for this focal length, where sharpness across the frame is very good. Finally at 200mm, good sharpness in the centre is still maintained at maximum aperture and fairly good sharpness levels towards the edges. Peak quality across the frame is attained at f/8 for this focal length and good sharpness across the frame is achieved.

Falloff of illumination towards the corners of the frame is reasonably well controlled. At 18mm and f/3.5, the corners are 1.5 stops darker than the image centre and visually uniform illumination is achieved by f/5.6 at this focal length. At 200mm falloff increases as the corners are 1.7 stops darker than the centre and visually uniform illumination isn't achieved until the lens is stopped down to f/11 at this focal length. Distortion is often an issue with high ratio zoom lenses like this. Imatest detected 6.13% barrel distortion at 18mm, which is quite a pronounced level and may pose issues in images with straight lines towards the edges of the frame. At 200mm 1.18% pincushion distortion is present, which is certainly less noticeable than the barrelling at 18mm. Luckily the distortion pattern is uniform across the frame, so correcting curved lines should be relatively straightforward in image editing software afterwards. Canon don't supply lenses at this level with a lens hood, which is a shame as the optional EW-78D petal shaped hood would be a welcome addition. Even without a hood, this optic seems reasonably resistant to flare and loss of contrast caused by strong light sources just outside the frame although the lens does seem more susceptible to flare at 200mm than 18mm. Shooting into the light can cause a loss of contrast, especially at 200mm.

Overall this lens offers a good quality compromise for those looking for a convenient alternative to carrying multiple lenses. Sharpness levels hold up well for a lens of this type and the four-stop image stabiliser greatly increases the usability of this lens making it a perfect travel companion. Although this lens isn't the cheapest of the bunch, the good build quality and optical performance will certainly make this a compelling choice when compared to the competition."... [Source]

Sigma 18-250mm F3.6-6.3 DC OS HSM
Announced on January 15 2009, the Sigma 18-250mm F3.6-6.3 DC OS HSM SuperZoom lens with a 13.8 times zoom ratio. This lens Hybrid Optical Stabilizer provides not only an anti-shake function for the camera body, but also compensates for image shaking in the view finder as the Optical Stabilizer is built in to the lens. This system offers the use of shutter speeds approximately 4 stops slower. The HSM (Hyper Sonic Motor) ensures fast and quiet auto-focusing. This lens has a minimum focusing distance of 45cm (17.7in) and a maximum magnification ratio of 1:3.4, making it convenient for close-up photography. Sigma also make this lens available in mounts for Sony and Pentax DSLRs, in additions to the Sigma, Canon and Nikon mount. 

The lens internal focusing allows users to fit angle-critical attachments like polarisers and graduated filters. Sigma's Hyper Sonic Motor (HSM), which is driven by ultrasonic waves, is built in to ensure quiet autofocusing at relatively high speeds. Super multi-layer coatings on the lens elements reduce the incidence of flare and ghosting. Extending approximately 100 mm from the camera body (without the lens cap attached), this lens protrudes a further 78mm when zoomed out to the 250mm focal length. The design consists of three barrels, the innermost containing the optical elements, the middle one engraved with 'macro' reproduction ratios that range from 1:3.4 at full zoom extension to 1:12.8 at the 18mm focal length. 

The Sigma 18-250mm F3.5-6.3 DC OS HSM SuperZoom Lens is currently selling at around $477.54, via Here are the review summary by SLRgear, gave a readers' overall rate of 8.67/10: "The 18-250mm provided sharp test results, even when used wide open, to about 80mm. Wide open in the telephoto range, things start to get a bit soft, especially in the corners. Stopping down helps alleviate these issues. At the wide end, the lens performs very well. At 18mm and f/3.5 we do note some slight de-centering but the central region is still very sharp at around 1.5 blur units. The corners are slightly softer at around 3 blur units. Stopping down improves this equation, until optimal sharpness is achieved at f/5.6; results at this aperture are between 1.5-2 blur units across the frame and essentially stay that way until f/11. Diffraction limiting sets in at f/16, and by f/22 the image is generally soft at between 3 and 4 blur units across the frame. In the mid-range - 24-50mm - the lens showed its best performance. Wide open at f/4 or f/5, the lens provides nicely sharp images, with around 1-1.5 blur units in the center but some softness in the corners (4-5 blur units). At 50mm the lens is balanced quite well, showing around 1.5-2 blur units across the frame. Stopping down to f/8 or f/11 improves any corner softness until the image is essentially smooth across the frame at around 1.5-2.5 blur units. 50mm is the ideal setting for the lens, providing the ''smoothest'' performance without corner softness; at f/8, it's the sharpest the lens gets, at just over 1 blur unit across the frame. Fully stopped-down performance is still acceptable by f/22, around 3 blur units, but at the extreme ends (f/32-36) we note generalized softness in the range of 4-5 blur units.

On the telephoto end, the lens shows its shortcomings. Wide open, it does a little better than previous Sigma 18-200mm offerings, but even by 80mm - just a third of the way through its entire focal range - it's showing significant corner softness wide open. Results at 120mm and 250mm are similar, with particularly soft corners at 120mm (9 blur units in the corners!). There also isn't much of a central area of sharpness to speak of; there's a bit at 80mm and 120mm, but by 250mm everything is slightly soft. Stopping down to a smaller aperture does help amend this softness, especially at 80mm; at f/8, it becomes respectably sharp, at just under 2 blur units across the frame. Not so much for 120mm and 250mm. At these focal lengths you'll need to stop down to at least f/11 to achieve optimal sharpness (2-3 blur units across the frame). Diffraction limiting sets in at f/16 so stopping down further only makes this less sharp. Fully stopped-down performance above 80mm (where you'll see apertures of f/36 or f/40) should be avoided, unless you like the soft-focus look: we note results in the 6-10 blur unit range, across the frame. 

Like most ''vacation'' zooms, the trick is to know the parameters where they function best. Sigma's latest iteration of this lens offers a bit more telephoto performance, for which the integrated optical image stabilization is crucially useful. Unfortunately the lens' maximum aperture decreases quickly as the lens is zoomed out, to the point where at 80mm, you're using a f/5.6 lens. This design allows the lens to be kept as small as it is, but at that point you're needing either a sunny day, an external flash, or a steady hand (even with the image stabilization) to get reasonably sharp photos. The testing on the lens shows it to be very capable when used in the wide-angle or mid-range settings, but telephoto performance leaves something to be desired. In all cases stopping down helps to improve the image, and using the lens at 250mm and f/11 only serves to underline the previous point. This is a walkaround lens, but really only if you're walking around outside on a sunny day. With those caveats, it's important to note that most lenses in this category have to struggle with the same limitations, and this lens perhaps comes out better than most. The whole point of the lens is to combine multiple lenses into one, and with the competitive price point, it serves the function admirably, with the side benefit of saving you a little money in the process."... [Source]

Tamron AF 18-270mm F/3.5-6.3 Di II VC PZD LD Aspherical (IF) MACRO
Tamron, originator of the superzoom lens more than a decade ago (Back in 1992, the AF 28-200mm F/3.8-5.6 Aspherical 7.1x zoom ratio lens), announced the AF 18-270mm F/3.5-6.3 Di II VC PZD LD Aspherical (IF) MACRO (Model B003) lens on December 9 2010. This 60th anniversary lens model is the world's most compact, lightweight lens with a 15x zoom ratio, featuring a 62mm filter diameter, and Vibration Compensation image stabilization. This is the second lens released to commemorate Tamron Co., Ltd.'s 60th anniversary. The SP AF70-300mm Di VC USD telephoto zoom lens was released in summary 2010.

Weighing in at 15.9oz., this new all-in-one zoom lens is equipped with an AF unit driven by Tamron's new PZD (Piezo Drive), an ultrasonic motor that delivers faster and quieter focusing when the autofocus is engaged. The 18-270mm Di II VC PZD is easy to use and highly portable - an all-purpose workhorse for any photographic situation. This Tamron 18-270mm f/3.5-6.3 Di II VC PZD lens have won the Lens of the Year award at the Camera GP 2011 Awards in May 2011, hosted by the Camera Journal Press Club of Japan.

The Tamron AF 18-270mm F/3.5-6.3 Di II VC PZD LD Aspherical (IF) MACRO lens is currently selling at around $649, via Here's the review summary by GearGuide, gave a rating of 3/5: "Given the $649 cost, one could make an argument that the Tamron 18-270mm F/3.5-6.3 Di II VC PZD is something of a value, especially when its massive focal length is factored in. Offering photographers several lenses in one, and a compact one at that, while focusing fast and providing mostly effective vibration compensation (well, sort of...), the Tamron 18-270mm F/3.5-6.3 Di II VC PZD is bound to be a leading temptation for many photographers looking to move beyond their kit lenses. But as we've pointed out, there are several caveats in making such a move. First one has to contend with variations in overall image quality throughout the lens' focal range, especially when it comes to sharpness. This lens' sweet spot is likely in the same area offered by the typical lens, and in this 35-70mm focal range the Tamron 18-270mm F/3.5-6.3 Di II VC PZD provides pretty decent sharpness and detail. At the wider and longer ends of the lens, things get less sharp, only rising to the level of average, which is somewhat unfortunate since we suspect these are exactly the areas that most photographers would be looking to exploit from a lens like this. Distortion is another tricky issue, barreled at the wide end, pincushioned at the longer end, photographers will have to keep an eye it one way or another through the lens' focal range. These issues may seem disconcerting, but we'll note again they aren't unique to Tamron, indeed the Tamron lens offers surprisingly similar performance as the competitors despite offering considerably more focal range, which is pretty impressive.

Because of its cost, its versatility, the compact size, and snappy autofocus, we feel reasonable in awarding the Tamron 18-270mm F/3.5-6.3 Di II VC PZD a "Recommended" rating to less advanced photographers so long as they understand what they're getting. We're confident that more advanced photographers and certainly professionals will want to move beyond the average image quality offered by such a lens, but for those content with good but not great image quality in a compact lens that can do just about everything, the Tamron 18-270mm F/3.5-6.3 Di II VC PZD might be the perfect fit."... [Source]


The built quality of the three lenses are quite similar with polycarbonate shells and solid rubber zoom and focus rings. The Sigma and the Tamron are supplied with a lens hood, while the Canon comes without hood, but you can easily purchase a lens hood for Canon at around $25. The Tamron has the longest reach at 270mm, while the Canon is the shortest at only 200mm. The autofocus of the three lenses are quite good, while the newly released Tamron 18-270mm comes with PZD (Piezo Drive) ultrasonic motor that should deliver faster and quieter focusing when the autofocus is engaged. According to Tamron, this PZD feature functions on the standing wave principle which utilizes high-frequency voltage to extend and turn the piezoelectric (piezoceramic) element, thus moving the entire element in a standing wave movement. Standing wave ultrasonic motors have the distinct advantage of being smaller than their traveling wave counterparts, and therefore allow a more compact lens size (Tamron 18-270mm lens is indeed the most compact among the three lenses). In terms of AF accuracy, the Canon and Tamron are more reliable than the Sigma, though again, they all performed good enough. In terms of noise, Sigma probably is the loudest of the three lenses. The image stabilization of these lenses allows to compensate about 4 stops of shake (as claimed by the manfacturers). Stabilization is definitely a big plus on the longer range of the focal length. In terms of price, the Tamron 18-270mm is the most expensive, while the Sigma 18-250mm is the latest expensive one among the three SuperZoom lenses. Here is the technical specifications comparison of the three SuperZoom lenses:


Canon 18-200 IS

Sigma 18-250 OS

Tamron 18-270 VC

Focal Length




Macro ratio

0.25x (1:4.0)

0.30x (1:3.4)

0.26x (1:3.8)

Max Aperture




Lens Construction

16 elements in 12 groups, including UD-glass and aspherical lenses

18 elements
in 14 groups

13 elements
in 16 groups

Diagonal Angle of View

74° 20' - 7° 50'

69.3° - 5.7°

75° 33' - 5° 55'

Image Stabilization





Lens motor (no USM)

Lens HSM motor

Piezo Drive motor

Closest Focus

0.45 meters

0.45 meters

0.49 meters


79 x 163 mm

79 x 101  mm

88 x 97 mm


595 g

630 g

450 g

Filter Size

72 mm

72 mm

62 mm

Street Price





August 26 2008

January 25 2009

December 9 2010

Which SuperZoom Lens to Choose?

As a matter of fact, if you're looking for a lens that will give you better image quality, you should probably avoid any of the above superzoom lenses as quality is sacrificed by giving you the conveience of a wide range of focal length. The main purpose and strength of superzoom lenses are to access the 18 to 200mm (or 270mm) range in a single lens saving you the hassle of changing lens when you need a wide range of focal length. I currently own a 24-105mm IS lens from Canon as well as the 70-200mm lens and the 24-105mm lens was staying on my camera more than 90% of time as my walkaround lens. If you are shooting mainly in the 18-55 OR 55-200 range and you don't mind changing lens, you really should look into getting the 18-55mm plus 55-250mm combo for better image quality and price.

To achieve the 18-200mm (or 270mm) range in a single lens, some compromise have to be make in certain setting in the lens. The key is to know the limitation and strength of different setting in your specific lens. For example, the wideangle performance of the Canon 18-200mm lens is distinctly mediocre due to a combination of barrel distortion, chromatic aberration, and softness at wide apertures; and while the lens is respectably sharp at longer focal lengths. You should then use the SuperZoom lens for the best of its settings. Overall, the Canon 18-200mm lens offers a good quality compromise for those looking for a convenient alternative to carrying multiple lenses. The IS system in the Canon lens is very effective. At 18mm, you can get a very good percentage of sharp images at .6 sec. and still getting sharp shots with exposures as long as 1 second. At 200mm, you can still get good results at 1/20 sec. with some even longer exposures resulting in sharp images. Auto-panning is featured (no switch required) - IS operation is barely audible. A relatively close 1.48' (450mm) Minimum Focus Distance delivers a .25x Maximum Magnification for the 18-200. While not a dedicated macro lens, this lens can also perform many close-up needs including flower and other small object photography. The Canon 18-200mm lens is far from perfect mainly due to the the absence of USM focusing, but it is a very likable lens with excellent responsiveness and stabilization and overall good image quality.

The Sigma 18-250mm is a good performer in terms of operation and ergonomics. The 18-250mm provided sharp test results, even when used wide open, to about 80mm. Wide open in the telephoto range, things start to get a bit soft, especially in the corners. Stopping down helps alleviate these issues. The HSM autofocus is fast, silent and positive, and probably on a par with Canon 18-200mm. The zoom action is smooth and even in line for a lens with such a long range. One of the major drawback of the Sigma 18-250mm is the performance of the optical stabilization system, which is probably the weakest link in this lens. It works reasonably well towards the wide end, giving about three stops benefit, but disappointingly is at its least effective at telephoto, where you can get at best two stops stabilization in real situation (Sigma claim providing a 4-stop advantage). Again, you should then use the SuperZoom lens for the best of its settings, and in this case use it in the wide end and avoid the telephone end. Unfortunately, most people purchase the SuperZoom lens is to make use of the telephone end of the lens and it defeat the purpose if the telephoto performance is not as good.

The Tamron 18-270mm lens is quite an impressive lens packing a 15x optical zoom range (the longest reach among the three lenses) and full set of features into such a compact body, thanks to the PZD (Piezo Drive) ultrasonic motor. The Tamron VC system is very similar to that of Canon's IS as both use gyro sensors to measure lens movement and move a group of elements to compensate. The effectiveness of the Tamron VC system on the 18-270mm zoom is somewhere around 3-4 stops at 270mm. Visually, the action can seem a little less smooth than that of Canon's lenses, but in testing it seemed equally effective at minimizing image blur. This lens' sweet spot is in the 35-70mm focal range providing pretty decent sharpness and detail. At the wider and longer ends of the lens, things get less sharp, only rising to the level of average. Overall, the Tamron 18-270mm is, for the most part, an improvement on the original non-PZD lens, especially concerning autofocus performance. It's now significantly faster and much quieter. It's pretty sharp in the center of the field, AF is accurate, the VC image stabilization works well and it's very compact. So if you were bothered by the autofocus performance of the old 18-270mm, it's definitely worth the upgrade. Another factor you should consider when comparing Tamron's to those of Canon & Sigma lenses is that the Tamron 18-270mm comes with a 6 year warranty. That's much longer than the 1 year warranty offered by Canon and the 3 years (1 year + 2 year extension) offered by Sigma on their lenses. Finally, deciding on which lens to use is a personal choice depending on preference and budget . All the reviews can serve as a guide but you will have to make you own decision. Enjoy your photo shooting!

DSLR Photography Latest Posts