DxOMark published their test results for the Tamron SP 15-30mm f/2.8 Di VC USD lens for Nikon F-mount ($1,199.00):
All lenses are a compromise, but the Tamron has a good balance, with high central sharpness wide-open and sharpness improving across the frame on stopping down, and with generally good control of chromatic aberration. On the downside, it has some slight field curvature at 30mm and it has quite high levels of both barrel and pincushion distortion that are more noticeable than the Nikkor equivalents.
However, at least the Tamron doesn’t exhibit complex distortion, so it should be relatively easy to correct with software. In physical terms, the lens is large and heavy and doesn’t cover the popular 35mm focal length, but as a 24-47mm equivalent on an APS-C-format DSLR, it remains a versatile offering. Combined with its good performance and the lure of built-in stabilization, at around $1,200 it looks very tempting.
