Whilst driving home this evening I had a thought that I wasn't sure of the answer.
Obviously I'm aware of pressure underwater etc.
but (for example)
(1) if I took my camera housing down to 20m and had an old analog depth gauge inside would the needle move
(2) what about in your drysuit ? Because wouldn't the drysuit surround you in an neutral atmospheric pressure
(3) if neoprene gloves worn under dry gloves (bungee installed to allow air to migrate), as you descend would the neoprene begin to compress
(4) if a 40m rated camera housing was installed with its only gas supply that acted the same way as an adv and opv from a breather. Would it then be able to go much deeper ?