Been tuning my quads to get smooth recordings. Several times had a perfect sounding/flying tune, but then the video was still shaky. Adding vibration damping to the camera helps a little, but doesn't solve the problem completely
Now Kabab posted this video showing the effect of an ND filter on the smoothness of the recording, and as you can see that does the trick.
At least I can stop getting lost on tuning for more smoothness, now that I know why I'm having such difficulty getting perfectly smooth video Need to find a filter that can fit on the Runcam Split camera, maybe the Mavic ND filters will fit, think I will try those first.