Dolphin Rebreather action.

[Mark Y]

Did some fun dives at Crosby 10/3 - 10/4. We had the place to ourselves Sat., two North Dakota divers on Sun.

Lk. Louise - 94 min., 122 max depth, used 22.5 c.f.
Menomin #2 - 52 min., 98 max depth, used 17 c.f.
Portsmouth - 60 min., 104 max depth, used 29 c.f.

Lk. Louise was alright. Started deep then worked our way up and around the whole lake.

Menomin # 2 had a bleak start. Just faceless muck with occassional branches, etc., then we hit a shear wall. That was really cool. Tough to think of it as a 'wall' compared to reef walls, but in a way, it was better, 'cause it was local.

Portsmouth - couldn't located the pipe so descended along a steep embankment covered with mucky laddened branches. It was black at 80 ft. and cave like at 100 ft. My cannister light worked real well (thanks John J). Very Lovecraftian, shapes just emerged from the blackness. Even the smell of the water managed to make its presence known. Smelled/tasted like swamp gas - Greg said sulfur. A really cool dive.

Lots of dive time left this year, use it wisely!

[Mark Y]

A few notes to my last post

(1) The dates are wrong, try October 4 & 5.

(2) The Lk. Louise dive was the first I had to end because I ran low on air, and the tank wasn't 100% at the dive beginning.

(3) For those people who ask me what there is to dive in Minnesota, wow, there's alot! It's hard to explain to a non-diver that low visibility & cold water turn them off right away. But for those of use who brave the colder waters, especially the North Shore (which has good vis), find Minnesota a dive paradise (OK, maybe I'm stretching it a bit, you know what I mean).

Mark Y

[Mark Y]

OK, last one.

Does anyone else 'out there' dive a Draeger Dolphin. This thread is getting rather one-sided and boring. What you all doing?

I know you're out there, as I've seen some of you diving.

Mark Y

[Chuck_Northrup]

Mark,

I just got back from Cozumel and did a weeks worth of diving there on my Dolphin. I decided to take the Dolphin rather than the Inspiration because I felt it would be easier to find nitrox than it would be to find high pressure O2.

I would have to double check my logbook to be sure but if I remember correctly I did 18 dives and I only used 4 aluminum 80's of nitrox. I brought my tank to tank equilizer with me and cascade filled off of the nitrox tanks. After the first few fills I was only getting about 2200 psi but that was still enough gas for two 1+ hour dives.

If I had one of Gordon Smith's Nano boosters, like John J, I would have been able to get full fills each time and probably would have gotten by with only 2 aluminum 80's. I do not want to start a RB vs. OC thread here, but the net result for my trip was that I only spent $40 on nitrox vs. the $180 I would have spent to dive OC nitrox for the week. Call it $25 worth of chemical used (just to be fair) and it is more like $65 vs $180.

Having been to Cozumel a number of times before (always on OC) I would have to say that I did notice a difference in marine life behavior being on the quieter system. I was able to find Splendid Toad fish by following their grunts, when I was right over them I could feel their grunts vibrating in my breathing hose. It was really loud! One of them actually attacked my macro framer, made for a better story than picture :-\ Sneaking up on Sea Turtles is always fun, they always look surprised when they finally see (not hear) you. The Spotted Drums and Queen Angle fish always seemed to shy away from me and my camera in the OC days. This trip they let me fire a plethora of pictures while completely ignoring me.

I was talking to our divemasters (at Del Mar Aquatics) about rebreathers and if they had seen many RB divers lately. They said they had seen a few but they were pretty rare. Rene was talking about a diver he had seen with "una caja amarilla" which could only be our beloved yellow box. There is one tech shop on the island that may be able to secure hp O2 called the Yellow Rose, but I am not sure about that.

Well, I am starting to digress so I'll end it here. The point is, yes there are other people diving the dolphin and it is a perfectly viable system which unfortunately is often overshadowed by the Inspiration. If you want the benefits of an RB and have no desire to go tech, I think it is the perfect system.

Safe Diving,

Chuck Northrup
Going Under Dive Center

[Mark Y]

Glad to hear you had good diving in Cozumel. Wish I could have joined you all!

I just returned from Florida where I put another 345 minutes on my Dolphin. Managed to squeeze in 6 dives in Pennekamp (including the Spiegel Grove & Benwood wrecks) & 2 dives off of Pompano Beach (including the Rodeo 25 wreck).

Looking forward to ice diving!

[freedivernd]

Being quiet is another + while free diving too... I've never been around a re-breather though.. are they as silent as free diving? There must be some noise... unless you're holding your breath too?
Fred

[Freedive WI]

Fred,
being a freediver, and certified on the Dolphin, I would say no.

The Dolphin still has some bubbles expelled from it and I remember hearing noises that the valves made. If nothing else, you can still hear your own breath as it moves through the loop. Having said that, a rebreather is still WAAAYYY quieter than OC.

While a Rebreather might cut down on the amount of gas used, my dive buddy just got back form Cozumel where he used zero tanks in a weeks worth of diving and hung with the scuba crowd the whole time. He was also allowed to zoom back and forth between different depth levels, which wouldn't work out too well on a rebreather. I bet it was nice not to be as dehydrated at the end of a dive, as compared to being on OC.

Now, back to rebreathers. ;D

Jon

[freedivernd]

Jon,
I didn't think a re-breather could be silent..

I saw your buddies video from Cozumel... fantastic! Would he mind if I put the link here.. under the freediving section? I checked over at wiscuba but didn't see any mention of it there.
Fred

[Freedive WI]

He won't care.

We might go spearfishing on Sunday, they say it's going to get above freezing down here, and I hope to shoot some more video that we could put on the Freedive-a-palooza site.

Jon

[Chuck_Northrup]

Fred,

What can I say; Jon is right on with his answer to that one. No rebreather, not even fully closed systems are completely silent. In fact by listening to the “noises” (a relative term here) your rebreather makes an experienced RB diver can distinguish between normal operation and sounds which indicate a problem. Bubbling from a rebreather is almost always a bad sign, especially when it is related to the posterior off-gassing phenomenon also known as Fast Acting Release of Transient gas (FART). :o

Holding your breath does not really change the noise level, except you will not hear the flapping sound of the check valves, nor does it significantly affect the amount of bubbles being released. That does not mean, however, that I do not find myself holding my breath from time to time while shooting photos. Old habits are hard to break! :

If you really want to see the difference between OC(open circuit), RB(rebreathers), and FD(free diving) maybe you can come down this winter and try an RB out in our pool. During our discover rebreather events I usually don only mask, fins, and snorkel so I do not disrupt the tranquility. Turnabout being fariplay, I could come out to Freedive-a-palooza and demonstrate my lack of Apnea skills. Then again with my ample bottom time (on the RB) maybe I would better serve the group as a safety diver? ;D

Safe Diving,

Chuck Northrup
Going Under Dive Center