As a DX lens this optic is designed specially for Nikon DX sensors. Its 35mm equivalent focal length is 27-202.5mm, making it a good, all-purpose lens, if not quite a superzoom. The lens has a plastic mount and, while some plastics may be tough enough to withstand space travel, on a camera, plastic is less desirable than a metal mount in our view. Still, it is built to a budget. The rest of the outer shell is also made of rigid plastic, which appears to be of good quality. The main external barrel has a large, rubber zoom ring and a smaller grooved focus ring, and as the zoom is extended, a further two plastic barrels extend.

Within the optical construction is a pair of aspherical elements, and one element made from Extra Low Dispersion (ED) glass. Focus is internal, so a polarising filter can be used, and a Silent Wave Motor is used to shift the elements quickly and quietly. At 385g the lens sits nicely on the smaller Nikon camera bodies, without causing strain on the mount, or on the user’s shoulder or neck. Like the Tamron 18-250mm lens the Nikon 18-135mm could hardly be said to be the fastest lens in the world, with a maximum aperture of f/3.5-5.6, but because of the shorter focal length range camera shake is pretty minimal in sunny conditions, though low light can cause problems with slower shutter speeds.

Image Quality
Let’s get the major complaint out of the way first, which is distortion. The lens has quite severe distortion at both ends of the optic, but even at mid-focal lengths images suffer. It’s not the worst we’ve seen, but it’s not ideal. After that, chromatic aberration is a fixture in high-contrast areas, especially in the corners, where it hovers at around the 1 pixel mark. This is visible on screen at 100% magnification, but less so in prints up to A4 size, so it can be deemed to be just about acceptable.

In terms of sharpness and resolution, the lens is pretty impressive – certainly in the central area of the image, which is excellent – and though the edges reduce the average somewhat, they are better than we expect for a lens at this price.