According to the GoPro website “The reason GoPro videos have a slight fish-eye effect, is due to the wide angle lens on the camera. It’s actually called a barrel distortion, which is a result of having the 170 degree lens. This curve/barrel distortion allows for the 170 degree ultra wide angle shots that GoPro is known for.”
Fisheye correction – tried it in Adobe After Effects cs6 – lens distortion, optics compensation. Reverse lens distortion put field of view to 65-75 50 -80 BUT cuts out part of shot, makes less good quality. PLus i like fisheye, ads to peice, like seeing through actual eye 170 degrees. much nicer after editiing fisheye in post production.