The official forums are surprisingly devoid of anyone trying this, which is not super encouraging.
I'd really like to experiment in doing some underwater VR180 photo/videography, I promise to share the results if anyone has any useful pointers (not strictly rPi related, but other platforms are even less promising. Happy for any unexpected hints tho!)
(Sorry for the barely-on-topic (if not outright offtopic)) but this is a rare chance to tap into HN's hive mind on this particular issue due to a Pi-camera related thread on the front page.