With that method I would just double check that 240-fps slo-mo video is synced to realtime. It may be applying an unnoticeable slow-motion effect (e.g. 90% spee

With that method I would just double check that 240-fps slo-mo video is synced to realtime. It may be applying an unnoticeable slow-motion effect (e.g. 90% speed playback) that would throw off the results So e.g. put a clock in the video