What is "recreational" rebreather, and any recommendations?

[JohnnyC]

Regardless of where you decide to go, you need to be aware that it's like learning to dive all over again. It's going to take a while to get used to it. On top of that, you've gotta be super attentive to your unit. People die when they get complacent. Do you think you'll be able to devote enough attention to your unit and your camera at the same time? Are you willing to leave the camera at home for the 50 hours or so it will take to not look like a complete idiot in the water? And are you willing to clip the camera off and forget about it for the next 50 or so any time something feels different, until you're completely comfortable with the unit and your performance?

It's not just a gear commitment you're looking at. It's an entirely new way of diving, mentally and physically. You're going to have to completely change your outlook on how you dive. You're going to have to become incredibly attentive to your own physiology. You're going to need to dedicate your attention to your gear tenfold over diving open circuit until you get really comfortable on the unit. It's a serious commitment do just learning how to be a rebreather diver, before you even consider carrying a camera with you again. It's not like learning to dive a double hose after coming from a single hose, it's like learning how to fly an airplane after driving a go-kart. It sounds ridiculous, but there are some pretty insidious ways that a rebreather can bite you that you need to come to terms with, so putting in pretty hyperbolic terms isn't really out of order.

 

[jgttrey]

I agree with this 100%. I won't retread the well-covered explanation of why "recreational" rebreathers are not what I would recommend. But, with the caveat that I'm a new-ish rebreather diver. I will echo and expand on the comment above about photography and expectations.

I have noticed a significant difference in my interaction with marine life, which is great. And, I appreciate the endurance and the fact that often gas consumption on OC goes way up if you're working hard with a camera, which is less of an issue on rebreather.

But, as @JohnnyC points out, this is learning to dive again. While there are advantages for you as a photographer - dive time, silence, no bubbles - there are significant new challenges. Not only in terms of task loading - you have a lot more to monitor and you cannot just tune out your CCR, but your buoyancy, trim, etc.

You will not be as nimble on a rebreather as you are on OC, at least I'm not. Pinpoint buoyancy control, essential to photography, is easy and unconscious when you can adjust with breathing. On a rebreather, particularly when shallower, every depth change is going to require some adjustment to lung and/or wing volume. That is your only way to stay neutral. All those hard won skills on OC where you can go up and down doing nothing but adjusting your breathing become irrelevant.

Buoyancy is "dynamically unstable," like balancing a broomstick on your hand. Not hard once you're used to it, but it is an additional task. You can't just zip up and down the reef chasing subjects as easily, at least not without periodically adjusting. Also, rebreathers, although they vary considerable depending on design and counterlung position, are often not as comfortable in unusual positions. You can certainly do it, but it's not quite as simple as OC to stand on my head taking pictures under a ledge, for example.

So, I would spend some time talking to CCR divers, and trying one - even get certified on one before buying, just to get a feel for this. I think it can be a great tool for those photography dives where it is needed, but most times, if I were taking pictures on a reef at 40', I'd have an easier time if I sidemounted a couple of 80s.

 

[guyharrisonphoto]

jgttrey and johnnyC, thanks for that insight. i certainly don't mind leaving my camera behind when trying new things (left it behind on my first 10 dives with the Kraken, and the first 5 dives with my scooter). The buoyancy issue is interesting to hear, for sure sounds like a learning curve there. I don't have any illusions that I will just jump in and dive like what I am used to. If it takes 50 hours to get comfortable, so be it.

Both of your posts also give me some practical questions. First, do you in essence become a "solo" diver once you are on a rebreather? I am comfortable solo, but more often I dive on dive charters with people I know. I (very) occasionally see a rebreather diver on these charters, but they always are diving solo. So, how does the rebreather affect how do you interact with your OC compadres in terms of air sharing, buddy awareness, things like that? What about dive boats--is there resistance to rebreather divers on them, or on liveaboards? I don't want to be limited to "special" rebreather trips, as I dive a lot (40-80 dives per year) and want to keep diving that way, basically whenever I feel like grabbing a boat.

What about the rebreather in shallower water? If I wanted to do a three hour muck dive in 16' of water but also wanted the silence, would it be suitable even though this is obviously an easy OC dive?

I don't see these practical questions asked very often, even though there is a lot of good info here.

Looks like the Poseidon, the Optima, and the AP Inspiration are readily available in my area. I am going to take a look at each.

Also, the idea of doing training on a rented unit before deciding to take the plunge sounds like a good one. Expensive, yes, but maybe better than going all in and then realizing it is not for me . . .

 

[doctormike]

Also, the idea of doing training on a rented unit before deciding to take the plunge sounds like a good one. Expensive, yes, but maybe better than going all in and then realizing it is not for me . . .

Not just that, but even if it IS for you, you will be in a much better position to decide what features you want and what you don't after you are a certified CCR diver.

 

[Jeremy Williams]

First, do you in essence become a "solo" diver once you are on a rebreather?

I think the general consensus is that you need that level of skill and equipment even if you are diving with a buddy. And it doesn't matter if that buddy is on OC or on a rebreather exactly like your own, the needs are the same up to the point that you are doing pretty technical diving and that becomes impractical.

What about dive boats--is there resistance to rebreather divers on them, or on liveaboards? I don't want to be limited to "special" rebreather trips, as I dive a lot (40-80 dives per year) and want to keep diving that way, basically whenever I feel like grabbing a boat.

For day charters, I think it's generally not a problem if you are driving to the boat. You can bring your supplies and all is well. If you are flying, or if you are on a liveaboard, there is some additional complexity. For a CCR, you need a supply of pure oxygen, and typically to get that O2 to the kind of pressure you'd like you also need access to an oxygen booster. Some liveaboards advertise this capability...

Rebreather-friendly liveaboard | Juliet Sailing and Diving

You have to do your research.

SCRs are often panned as inferior to CCRs, but one of the big advantages of an SCR is that it uses a tank of the same nitrox that you're diving on OC today. It has other traits that I dislike, but that's a significant advantage.

I'd suggest that you pick up Mastering Rebreathers by Jeff Bozanic.

Best Publishing Company - Mastering Rebreathers, 2nd Edition

 

[jgttrey]

Both of your posts also give me some practical questions. First, do you in essence become a "solo" diver once you are on a rebreather? I am comfortable solo, but more often I dive on dive charters with people I know. I (very) occasionally see a rebreather diver on these charters, but they always are diving solo. So, how does the rebreather affect how do you interact with your OC compadres in terms of air sharing, buddy awareness, things like that? What about dive boats--is there resistance to rebreather divers on them, or on liveaboards? I don't want to be limited to "special" rebreather trips, as I dive a lot (40-80 dives per year) and want to keep diving that way, basically whenever I feel like grabbing a boat.

Rebreather divers are no more, or no less, solo than their OC counterparts, which is to say I don't think being on the rebreather makes that big a difference as to whether you are comfortable going buddy-less. Except that I'll say that compared to a single cylinder OC diver, there is a level of redundancy a rebreather diver has, since they have bailout - a completely independent system that doesn't depend on a nearby buddy. I'd be more comfortable solo on CCR than single cylinder OC.

No reason you can't buddy up with an OC diver, except you'll find yourself limited by their gas duration and dive profile. Air sharing is no problem, since you have bailout to share if they have a problem. It is recommended that you spend some time ahead of the dive with an OC buddy to teach them what to look for with you, as helping a CCR diver is different than helping someone on OC. But, you'll get a feel for that in training.

As noted, you just have to check with the boat. Some fully support CCR, some tolerate it if you are self sufficient on supplies, and some don't do it at all. It's just one more question to ask.

What about the rebreather in shallower water? If I wanted to do a three hour muck dive in 16' of water but also wanted the silence, would it be suitable even though this is obviously an easy OC dive?

Sure, it works fine. Just remember that when you're shallow everything about buoyancy is more demanding, particularly on CCR. So, a constant 16' feet is much less demanding that going back and forth between 8' and 16'. You'll see this with rebreather divers on shallow reefs - they tend to swim around coral heads, keeping the same depth, rather than going up and down over them.

Like everything it gets easier with practice, especially once you learn how to stay ahead of the unit. Again, you'll get a feel for this during training. Just swim from the shallow end to the deep end and back a few times and you'll see what I'm talking about.

 

[doctormike]

So, how does the rebreather affect how do you interact with your OC compadres in terms of air sharing, buddy awareness, things like that? .

in case any of you can make it to Secaucus, NJ by 8 PM tonight...

 

[Storker]

I dive a Kraken now and really love it (have about 100 dives on it). The no-bubbles-in-your-face experience is just great. But, they are not quiet and can scare off animals similarly to a standard reg . . .

I have no dog in this fight and have absolutely no knowledge of rebreathers.

But I just wanted to mention that one of the best UW photogs in my part of the world dives a rebreather for exactly the same reason you seem to have for considering going to CCR. It isn't for me, though, but that's quite another can of worms.

 

[Vicko]

I'm one of those people. I just really enjoy rebreather diving. I like the science, the gear, the quiet, the gas efficiency, the deco efficiency. I like not carting around two sets of doubles and deco bottles every weekend. I just like talking about them and reading about them. Switching to CCR has really revitalized my interest in diving.

That's not really recreational, I was more thinking of people who never go past their mod1 training.

 

[tomfcrist]

But I just wanted to mention that one of the best UW photogs in my part of the world dives a rebreather for exactly the same reason you seem to have for considering going to CCR.

The best UW photographer in my part of the world used to dive rebreathers as well. We all know how that turned out.

The “shot” can never be so important that you forget about your anesthesia machine on your back. And bailout getting in the way of the camera is a dumb reason to dive without it.

I worry more about photographers on CCR than anyone else. I feel the likelyhood of taskloading overpowering basic safety is greatest with a big ass camera in hand.