PetaPixel has posted an article about Ian and Erick Regnard who are shooting 4 x 5 Polaroid images underwater. The Mauritian photographers have designed and built a specific camera and rig in order to capture their images.

They also had to do extensive testing to figure out the focus distance of the camera with various lens settings. Perhaps most awkward is the fact that they can only shoot one image at a time before needing to add a new frame on the boat.

You can see more of their work on their website. All images by Ian and Erick Regnard.