I haven't been very impressed with the clarity of the underwater shots I have got with a GoPro (which got lost at sea near Newcastle) or the Sony Action Cam I got to replace it. If you don't know what a GoPro is, check out this and this.
We have been following a sailing blog called S/V Totem, which we strongly recommend. It is a lovely story of a family with three kids who are sailing slowly around the world. The mother Behan takes beautiful photos, including underwater ones. She has set a standard which I aspire to emulate.
So I bought a little Olympus Tough TG-2 camera which can go down to 15 metres, and we used the opportunity of arriving at a good dive spot on Hayman Island to try it out.