It’s a little dark to see all the tricks. I think that window in the background is making your camera adjust the contrast to make it a darker video. Next time you shoot a video, try having a window to the outside in front of the person yo-yoing instead of in front of the camera. So have the camera in front of a window pointing inside at a wall.
^^ actually we had the room really bright and when we uploaded it to the computer it was fine but after YouTube upload it darkend for some reason. also anybody have any suggestions for how to make a better video?