Excerpt: Gary Wolstenholme gives the Sigma 50-200mm a look over with his expert eye. Sigma 50-200mm f/4-5.6 DC OS HSM: Handling and features After purchasing a DSLR, many people will add a telephoto zoom to their kit bag at some point in time. Priced at £200 with optical stabilisation included, which promises to tame camera shake, this lens is bound to be a popular choice for those looking to extend their zoom range beyond the standard 18-55mm kit lens.
Excerpt: Designed specifically for APS-C cameras with smaller than full-frame sensors, as denoted by its 'DC' suffix, the Sigma 50-200mm f/4-5.6 DC OS HSM zoom lens is available in Canon, Nikon, Pentax, Sigma and Sony mount options. Once you take the crop factor into account, the effective zoom range is 75-300mm in all versions apart from Canon-fit, where it's 80-320mm.
Pros: Small but not too lightweight, HSM autofocus and optical stabiliser, Includes a focus distance scale, often omitted on budget lenses
Cons: Lack of outright sharpness at 200mm focal length, Stabilisation only consistently gave a 3-stop advantage in our tests, Not compatible with full-frame cameras