Sharpness at 18mm

The sharpness tests for this review were carried out using a real-world subject rather than a test chart. The Nikon AF-S Nikkor 18-140mm f/3.5-5.6G VR lens was attached to a Nikon D7100 body, which in turn was mounted on a sturdy tripod. We also used an infrared remote release and mirror lock-up to prevent any blurring that may result from camera or mirror movement. The 100% crops represent about 1/600th of the total frame area.

The full frame at 18mm

Centre sharpness is quite good at f/3.5, and improves further upon stopping down to f/5.6. On a 24-megapixel DSLR such as the Nikon D7100, the effects of diffraction become visible at f/8 but do not become a serious problem until you hit f/16. The f/22 setting is best avoided.

The borders, while commendably sharp, suffer from a lack of contrast – especially at f/3.5 and f/5.6. Sharpness peaks at f/8 and f/11.

Aperture	Centre Crop	Edge Crop
f/3.5
f/5.6
f/8
f/11
f/16
f/22