Best superzoom for Canon DSLRs: 8 tested

Sigma 18-250mm f/3.5-6.3 DC OS HSM - £400

The newest and mightiest of Sigma's superzoom lenses, the 18-250mm is pretty much the same size and weight as the company's older 18-200mm OS lens and has the same 72mm filter size, yet offers three key advantages.

First of all, the effective telephoto reach extends to 400mm instead of 320mm. Secondly, that reach is made all the more usable in handheld shooting thanks to the inclusion of Sigma's latest generation 4-stop image stabiliser, which works a treat.

Finally, the lens comes complete with HSM autofocus, which we found to be much quieter and a fair bit quicker than with either of Sigma's 18-200mm lenses. Even so, autofocus is only a bit quieter and not much faster than with the Canon superzooms. Overall build quality is very good and, for a relatively heavy lens, zoom creep is minimal.

The lens proved sharper than the Canon lenses, especially at wide aperture settings. Distortions were less pronounced as well, compared with the Canon 18-200mm and Sigma 18-200mm lenses. For power and versatility, this is the best Sigma lens in the group and a better buy than either of the Canon lenses.

18mm sample image from the Sigma 18-250mm f/3.5-6.3 DC OS HSM

250mm sample image from the Sigma 18-250mm f/3.5-6.3 DC OS HSM