Swimming with Whales in Vava'u Tonga while on a tour with Dolphin Pacific Diving. Video shows a mother and her calf on 15 October, 2009. Read about the trip at blog.stevesadventure.com/2009/10/swimming-with-whales-absolutely-amazing.html
This video is NOT in slow motion. The whales are just gently moving. It was shot with a Canon A710 still camera in an underwater housing.