I gave up underwater still photography when my beloved Nikonos V leaked a decade or so ago. Since then, I focused solely on underwater video. ( You can see a sample of my video work at http://www.peterwalk...nderawasih.html )
But, when I read about the RX100 and the Nauticam housing, it seemed like here might be a camera small enough without too much quality trade-off to take along on video trips. It needed to be small and light enough that I could pack it with the video camera and housing and it needed to use the my video Sola 4000 lights/arms instead of strobes.
So I put together the combination of a Sony RX100 (set to RAW), Nauticam housing and Sola 4000 light with locline arm on a tray. Tried it earlier this month at Fish Rock at South West Rocks on the New South Wales north coast.
Take a look at the results: http://www.peterwalker.com/swr.html
All the shots were taken by the RX100, except the first one.
IMHO, not bad.