Tamron had an ambitious goal with the Tamron 18-200mm f/3.5-6.3 Di III VC, promising both wide-angle and telephoto focal lengths in a compact package for mirrorless cameras. It also comes with Tamron’s brilliant Vibration Compensation (VC) system and fast stepping AF motor.
It’s not a fast lens by any stretch, with f/3.5 being the maximum aperture, and it’s not all that cheap, either, although Sony’s own equivalent 18-200mm lens is more expensive.
The Tamron 18-200mm f/3.5-6.3 Di III VC comes in Sony E-mount for NEX and Canon EOS M mount, and is designed to be an all-in-one lens that goes as wide as 18mm but also zooms in to 200mm. The equivalent focal length on a full-frame camera is 27mm at wide-angle, and a full 300mm at the telephoto end.
This lens would be an ideal choice for general purpose photography covering everything from landscapes to portraits, but does this versatility come at the cost of image quality? That’s what we’re here to find out, so let’s see how this impressive-on-paper lens performs in the real world.
Design
The Tamron 18-200mm f/3.5-6.3 Di III VC is nicely built and comes in silver and black or a plain black finish. While quite a lot of the lens is made from plastic, it has a metal coating and lens mount which helps to make it feel solid and durable.
It weighs 460g and is 10.2cm long, which makes it considerably larger than the 18-55mm kit lens supplied with Sony NEX cameras. This makes the camera and lens combo very unbalanced and front-heavy, but until mirrorless camera zoom lenses can be made smaller, it’s going to be something mirrorless shooters have to live with.
The minimum focusing distance of 45cm is typical of a lens in this focal length, so although it’s no macro lens, it works well to fill the frame at 200mm.
Focusing is done internally on the Tamron 18-200mm f/3.5-6.3 Di III VC, which means the 62mm filter thread doesn’t rotate. That makes this lens great to use with graduated or polarizing filters.
Optically, this Tamron lens is built with 17 elements in 13 groups, which is quite impressive although it adds to the weight and size. Seven rounded diaphragm blades complete the line-up, and the maximum aperture is f/3.5-6.3 while the minimum sits at f/22-40.
The Tamron 18-200mm f/3.5-6.3 Di III VC sounds good on paper and feels good in the hand, but what’s it like in the field?
The Tamron 18-200mm f/3.5-6.3 Di III VC in Use
The autofocus drive features a silent stepping motor that works brilliantly for the Contrast Detection AF system. The quietness of the AF motor makes this lens a good choice for video shooters and for candid street photography. Focusing speed is decent but not brilliant, but the AF does tend to hunt for focus quite a bit at the telephoto end of the range.
The Vibration Compensation system makes up for the lack of a big maximum aperture a bit. the system allows for sharp images to be taken most of the time at 1/40th second and around half the time at 1/20th second, which is about four stops slower than a lens without image stabilization.
Manual focus is made easy with the wide focusing ring, which offers a good amount of resistance to make small adjustments without problems.
Let’s take a look at the sharpness and image quality of the Tamron 18-200mm f/3.5-6.3 Di III VC. High-ratio zooms like this are typically sharp at short focal lengths, but it drops as the lens zooms in. The Tamron 18-200mm is no different in this respect, with center sharpness outstanding at 18mm and maximum aperture, and very good edge sharpness at these settings too.
The peak sharpness of this lens is found between f/5.6 and f/8, with clarity all across the frame. When zoomed to 70mm, there is a loss of sharpness in the center, but it’s still excellent between f/5.6 and f/8, and edge sharpness is still good.
At the 200mm extreme zoom end of the range, center sharpness drops again but is still pretty good, while edge sharpness deteriorates more. At this focal length, f/11 is the aperture where peak sharpness quality is achieved.
Chromatic aberration is well-controlled at shorter focal lengths, but fringing increases as the lens is zoomed in, with it being worse at 200mm where it becomes visible along high-contrast edges.
Vignetting is not much of an issue with the Tamron 18-200mm, and although distortion is quite strong at 18mm, it’s practically non-existent at 200mm, and this type of distortion is easily corrected in image editing software like Lightroom or Capture One.
How Does It Compare?
Sony’s native version of this lens, the Sony E 18-200mm f/3.5-5.6 OSS LE costs more than the Tamron, but is the extra price justified? The optical performance between the two lenses is almost identical, but the Tamron 18-200mm is sharper in the center at longer focal lengths, and the ghosting control is better than the Sony E 18-200mm.
The Sony E 18-200mm performs better on lens distortion, but the bottom line is that the Tamron 18-200mm is better value for money and just as good. If you are looking for more Sony lens options, then there are several great Sony zoom lenses you can buy for under $1000.
| Tamron 18-200mm f/3.5-6.3 Di III VC | Sony E 18-200mm f/3.5-5.6 OSS LE | |
| Optics | 17 elements / 13 groups | 17 elements / 13 groups |
| Diaphragm | 7 rounded blades | 7 rounded blades |
| Minimum Focusing Distance | 50cm | 50cm |
| Aperture | f/3.5 – 6.3 | f/3.5 – 5.6 |
| Weight | 460g | 524g |
Conclusion
While the Tamron 18-200mm f/3.5-6.3 Di III VC is not going to be brilliant in low light conditions due to the f/3.5-6.3 slow aperture, it’s a very useful lens with outstanding overall sharpness in the f/5.6 and f/8 range and good sharpness in most of the rest. Barrel distortion may be a problem with this lens, but it can be corrected easily enough.
The Tamron 18-200mm is a very useful lens with a huge focal range, which makes it ideal for travel photography or for those who don’t intend to change lenses very often. If you can only afford one zoom lens for your Sony, then the Tamron 18-200 is an excellent choice, and cheaper than the Sony E 18-200.
