The Other (under) Side of Rolling

I've been trying to watch and capture what goes on under water when someone sets up to roll. The set up is the start of it all, and mispositioning here can kill the entire deal.

I am looking to see the position of the paddler, especially their shoulders and how  perpendicular they are to the surface. I also look to see if the paddle is above the surface and, thus, not visible in the image. Eventually, I want to use video mode to follow the path of the blade during the final stage of the roll.

I am sure others have done this and have done it better than I will. but, hey, it's winter and a guy needs something to pass the time.

Paddle safe...
DS