OM System TG-7 + PT-059 housing + Backscatter air lens

OM System TG-7 (formally Olympus)

The TG-7 is one of the best compact cameras ever made for underwater photography. The camera itself is waterproof down to 15m which is amazing protection in case you ever have a problem with an underwater housing leaking. It contains really useful underwater modes to help with the colour and the macro mode (they call it microscope mode) is incredible.

OM System PT-059 (formally Olympus)

The OM System housing for the TG-7 feels good in your hands and allows you to access every feature of the camera in a logical way. The front port has a 52mm filter thread for attaching external “wet” lenses. It comes with an adapter with a fibre optic port for attaching a standard Sea and Sea type fibre optic cable. It is depth rated to 45m.

Backscatter air lens

This lens has a 52mm thread for attaching to various compact camera housings though it is particularly useful for the Olympus/OM System TG series . It is a “wet” lens meaning you can fit or remove it when underwater. In fact having water between your housing’s port and the rear element of this lens is important, and you especially don’t want to have air bubbles in between. It is always best to get into the water without the lens attached, both to deal with the bubble problem but also to make your system lens vulnerable to damage as it hits the water surface on entry. 

This lens restores the camera’s angle view you’d get on land when you are underwater. Whereas normally when you go underwater with your camera’s lens behind a flat port you get a magnification effect of about a third. This is not a massive increase in your angle of view but it is still much better than not having it at all. For the Olympus/OM System TG series of cameras it’ll give you an angle of view of around 80 degrees when underwater

There are other types of lenses that give you a much wider shot, but these do cost more money and are heavier as they contain far more glass.