A group of dedicated wildlife photographers recently tested the new Falcon 300mm telephoto lens. With it, they were able to capture stunning images of birds that were only seen as blurred shapes through their 200mm lenses, despite the 200mm lenses having a larger aperture and gathering more light than the 150mm Falcon lens. Based on these photographers' experiences, any serious wildlife photographer should choose the Falcon lens if they are looking to photograph birds. Which one of the following most seriously weakens the argument?