Tamron SP AF 10-24mm f/3.5-4.5 Di II LD Review

As good as consumer digital SLRs have become, one area that frustrates wide-angle lovers is that the crop factor of an APS-C sensor effectively increases the focal length of the lens.
While wildlife and sports photographers generally see this as a benefit when they’re using telephotos, it’s a real hassle for those trying to fit a wide area of a scene into the frame.
In the days of 35mm film, the 16-35mm was the most popular choice of ultra wide-angle zoom lens, but stick that on your APS-C DSLR and it effectively becomes a 24-52mm 
(or 26-56mm on a Canon EOS body).

However, the emergence of digital SLRs has seen the development of a new generation of ultra-wide lenses, covering ranges like 11-18mm or 10-22mm, all offering fresh wide-angle options to the DSLR photographer. Tamron’s 11-18mm was a decent enough lens, but the extended coverage of the 10-24mm is sure to make it a more popular choice, as it effectively covers 15-36mm (16-38mm with Canon).
The lens is compact and feels very well made, with the wide, textured zoom ring offering an easy grip and smooth action. 
The wide manual focus ring is found towards the front of the lens, and it too has a smooth action. The design has been updated, with an attractive black finish with gold strip, and owners of a collection of 77mm filters, who are thinking of upgrading from the Tamron 11-18mm, will be glad to know that these will fit this newer lens as well.

The lens sees several internal developments over the 11-18mm, aimed at providing an improved optical performance. As well as a glass-moulded aspherical element, there are three hybrid aspherical elements, a pair of LD (Low Dispersion) elements and an HID (High-refractive Index) glass element; all working together to minimise aberration and distortion. The lens surface multi-coatings have been improved to minimise internal reflections, ghosting and flare, all of which degrade image quality.

Autofocus isn’t usually a problem with ultra-wide zooms and this proves to be the case with the Tamron, which rarely had problems zipping positively and quietly into focus. If you use filters, you’ll be glad to know that the Tamron has an internal focusing system, so your filter doesn’t rotate as the lens focuses. In terms of sharpness, the Tamron provides a very good overall performance throughout its range.
At maximum aperture, detail is good and improves to excellent at f/8-13, which is where the lens performs best. Colour fringing, common in wide-angles, is sometimes evident towards the edges of the frame when shooting subjects with a straight edge, but shoot in Raw and you can minimise any trace of it when processing your Raw files. Overall, the Tamron delivers a very good, all-round performance.

Verdict
The Tamron lens handles nicely and delivers very good results. Its extended range, and features such as internal focusing and, of course, high-quality optics, mean that it’s certainly one to add to the shortlist. Sigma's 10-20mm is the current number one choice as top value ultra-wide zoom, but is set to face a strong challenge from the Tamron, especially if the 10-24mm lens  falls in price to be even more competitive.