If manufacturing, design and economic constraints were not issues, the perfect lens would cover a huge range of focal lengths, from wide angle to long telephoto and a very wide, constant maximum aperture would be always available.

took the plunge and not regretting, great lens. Everything about it is perfect; lens caps, buttons, build. Pics are super sharp and with only a 5Ti I'm thrilled; walk around the house I haven't taken it off for 4 days now.

Available in Canon and Nikon mount options, Tamron's latest all-in-one ‘superzoom' lens comes closer than most to that goal, stretching from fairly generous wide-angle coverage to an unprecedented 400mm ‘super-telephoto' focal length – on Canon and Nikon APS-C format bodies, that's equivalent to...

Class-leading telephoto reach; Mighty zoom range

Lacks the Tamron 16-300mm's wide-angle potential; Focus ring rotates during autofocus

The Tamron 18-400mm f/3.5-6.3 Di II VC HLD covers an incredible zoom range, from wide angle to super telephoto, and while it doesn't match lenses with shorter ratios in image quality, it betters them in convenience.

22.2x zoom ratio; Solid image quality; Image stabilization; Moisture-resistant design; 1:2.9 macro magnification; Available for Nikon and Canon SLRs

Wide-open performance suffers beyond 300mm; Shows some chromatic aberration at longer focal lengths; Visible distortion; Focus ring rotates during AF

Powerful performance that exceeds your imagination. Introducing the world's first ultra-telephoto all-in-one zoom with a 22.2X zoom range. Now you can shoot everything from vast landscapes to details of a bird with a single lens.

After doing a lot of homework looking up this lens, I decided to purchase it. I've not been disappointed! I have had it for a several months over the summer and into the winter taking a variety of shots and been very pleased with the results.

Durable; Great Picture Quality; Versatile walk about lens

The Tamron 18-400mm lens is a fun interchangeable lens that will serve you well for many different types of photographs. You'll be amazed at the different types of looks you can achieve through the wide focal range of this lens, which makes this model a great lens to take when traveling.

Amazing focal range; Low price tag versus other large zoom lenses; Both Nikon DSLR and Canon DSLR versions available; Improved image quality throughout range versus previous Tamron zoom lenses; Easy to use controls on the lens; Lens moves through its zoom range smoothly; Reasonably good autofocus...

Image quality not good enough for advanced photographers; Noticeable barrel distortion at smallest focal length; Slight sharpness problem at maximum focal length; Some sharpness issues at high f-stop numbers; Some chromatic aberration problems; Not really a weatherproof model

I had to wait for this as it was a special order but it was well worth it. I hated having to carry more than one lens and now I don't have to. It takes great close-ups, great distance shots and of course everything in-between.

Tamron's latest DSLR superzoom offers every focal length that most photographers will need in one lens. But is ...

Good levels of sharpness for a superzoom; Customisation via optional console; Built-in vibration control

Fringing can be noticeable at 300-400mm; Only available for Canon and Nikon APS-C DSLRs; No focus distance on lens barrel

Versatile lens if you only want to carry one lens. A little heavy, so it takes some time to get used to.