Motion Tracking Using A Witness Camera

Back in 2015 ish I was trying to come up with a way to better track shaky or fast moving shots that had a tight FOV, without resorting to manually tracking frame by frame ( I was using After Effects at the time ).

I had the thought of using a witness camera that would film the same shot, just at a wider angle. My theory was that you could then motion track the wider shot - which would naturally appear less shaky and chaotic due to its wider FOV, as well as contain more info to track against - then translate that track on to the tighter shot.

To test the concept, I mounted both a GoPro and a Sony FS700 ( with a 105mm lens ) to the same shoulder rig and filmed a quick test.  I then tracked the GoPro footage in AE to create a virtual camera which I then manually zoomed and repositioned to match the Sony footage. There was probably a way to perfectly translate the track if I was better at math and knew the exact lens info and placement relative to each other and the subject BUT... it was just a proof of concept which worked well enough with a not-so-great track for me to say, "Yeah, it can be done."

Below is that result, tracking the 2D TEXT element to sit in front of the computer screen. I wound up never needing to use this solution on a project.