GoPros are awesome little cameras for thrill-seekers looking to document their adventures, but there are plenty of filmmakers that put them to work on their projects, as well. They're cheap, small, light, and can record in 4K, which make them excellent b-roll cameras when you need one in a pinch; the only problem with that, though, is the lens distortion. 

In order to do what they're made to do, GoPros capture an extremely wide field of view resulting in fisheye distortion, which is no good when all of your other footage doesn't have any. But, you can fix it in post (did I just say that?) and if you use HitFilm, you can do it in under 20 seconds. Just follow this crazy short tutorial from Aidin Robbins.

Don't worry if you don't use HitFilm to edit your work; the process is just as easy in any other video editor. For those who are using Premiere Pro, all you have to do is go to the Effects panel, choose Video Effects, Distort, and then drag Lens Distortion onto your clip. From there you can adjust the Curvature slider in the Effect Controls panel until you remove the unwanted distortion. 

Boom. You're done!

Source: Aidin Robbins