What is on their backs?

[pjones]

I was surfing the Youtube and came across this video of Diving with Manta Rays...

YouTube - Diving with Manta Rays

I thought at first that they were diving with rebreathers but then noticed at a number of instances throughout the video that there were bubbles coming from their mouths. is this an "all in one" type bundle that there wearing? or is it that rebreathers actually expel gas at some point through their operation? It was always my understanding that rebreathers recycled the air and produced no bubbles..... however the more I think about it now the less that sounds correct since (if I understand correctly) in order to dive at different depths the mix needs to be adjusted and the added gas would need to displace existing gas.

Maybe its just my understanding about rebreathers that needs to be corrected....

Thanks

 

[Tortuga68]

There are Semi-Closed Circuit Rebreathers (SCR) as well as Closed Circuit (CCR). The mix is adjusted by the rebreather in the breathing loop

 

[scuga]

Maybe they are semi-closed circuit rebreathers?

 

[CalgaryDF]

It looked like they just had regular open circuit regulators. Perhaps they are wearing some sort of tank backpack that is streamlined?

They definitely aren't wearing normal looking scuba gear, but I think that they are still on open circuit.

 

[vondo]

The lower right corner says Cousteau. They're well known for using tanks encased in a shell because it looks cool. My guess is that this is just regular open circuit scuba.

 

[pjones]

I've come across some more information that holds the answer to my question. It looks like its a system that utilizes both CCR and open circuit.

Equipment | Ocean Futures Society

Thats really cool! I've never seen anything like it before.
Thanks to those who have posted such a quick response already

 

[scuga]

so they have 3 30's and a CCR under the hood? thats amazing.

 

[tc]

That looks like an updated version of a tank system they used decades ago- It was basically three smaller (30ish) tanks manifolded together inside a plastic case.

I'll see if I can find a pic.

 

[tc]

Check the photo's at about post 64/65- I think the ones you see are an updated version of these.

http://www.scubaboard.com/forums/vintage-equipment-diving/63188-triple-tank-triple-manifolds-7.html

 

[diversteve]

They're open circuit systems with small tanks under a cover. If you want to know more about them, PM [user]Blair Mott[/user] that's probably him holding the light in the video. He's been their Chief Diver for over a decade.