Tamron's early ultra-wide for Nikon DX — the 11-18mm f/4.5-5.6 covering 16-27mm equivalent.
The Tamron SP AF 11-18mm f/4.5-5.6 Di II LD Aspherical IF was released in 2005 as one of the earliest third-party ultra-wide zooms for APS-C DSLRs. Covering a 16-27mm equivalent range on Nikon DX, it provided affordable ultra-wide access at a time when options were limited. The SP designation indicates Tamron's premium build tier.
Optical performance is decent for the era. Centre sharpness is acceptable. The LD and aspherical elements help control aberrations. The slow variable aperture limits low-light use. As an early ultra-wide zoom design, it represented good value when first-party options were significantly more expensive. IF design prevents front element rotation.
Nikon F mount, APS-C. Filter thread is 77mm. Weight is approximately 330 grams — lightweight. Build quality is solid SP tier. No image stabilisation. Internal focusing keeps the front element stationary. The 11mm wide end on APS-C provides a dramatic 16mm equivalent — enough for most wide-angle photography.
Very affordable on the used market. Check zoom and AF operation. Thoroughly superseded by modern alternatives. Only worth considering at very low prices. The Tamron 10-24mm and Tokina 11-16mm f/2.8 are significantly better options. A piece of early APS-C ultra-wide zoom history.