There are some awfully impressive lenses available on the market right now, but many of them are prohibitively expensive, and that has allowed a range of third-party manufacturers to fulfill the needs of countless photographers and filmmakers with more affordable options. Once such company is Sigma, and their new 70-200mm f/2.8 DG DN OS Sports lens looks like quite a winner. This excellent video review takes a look at the lens and the sort of performance and image quality you can expect from it in use.