You push in so slowly and made sure not to move the camera / gimbal up and down to jostle the viewers perspective. This is the way slo mo should be done.
Plan your flight path in a straight line and do not yaw or rotate.
What is really cool is to fly a straight line from farther back at a set value at the higher frame rate and then start the slow motion. So it zips up to the subject. Waterfall in your case and then focuses on the point of interest with an intense slow motion.
That has to rate in my top 5 favorite videos from this site. It is absolutely beautiful, we don’t get anything that beautiful in Austin Texas during winter. I’m gunna save this to show my wife and 2 girls. Wife is gunna trip out over how great the camera is and then you get such a awesome waterfall with the snow on the sides and middle, with water flowing under it. I’m sorry in advance for my next comment, I really hate you fricken north people, you get real winters with the real beauty.