100-400mm zoom lenses are some of the most popular out there, offering a highly versatile focal length range suitable for just about everything from wildlife photography to sports and more. There are many versions of such lenses at a wide range of prices, with the Canon RF 100-400mm f/5.6-8 IS USM sitting at the budget end of things, and this excellent video review takes a look at the sort of performance and image quality you can expect from it in real-world usage.