The only solution is better light, and a lot. 960fps is a lot of frames per second. So not enough light will come through indoors, most of the time. Go outside and record a bird, or a car driving by, and it will look great.
Seriously, look up the X-men Movie, days of futures past, and look for how they did they did the scenes for quicksilver. They had SO MUCH light on him that they had to actually take breaks because it got to hot.
This is is a common issue with slow motion. Some cameras are definitely better than others, but the only real fix is to have proper lighting.
Exactly right. I had found an animation online to show someone how slow motion works. Once they saw the process, they understood... and ended up making some really awesome vids. 😊