Master.........Really?

[Landstander]

The Self-Reliant diver course is nothing like the way things used to be, when courses were so wonderful and the fatality rates for divers were several times higher than they are today. For example, it requires the student learn to carry and use a redundant air source, something that was never a part of the marvelous training back in that golden age.

As for how much money PADI makes on a Distinctive Specialty course and how the course is priced, Colliam7 was exactly right. Once the course has been approved and the instructor certified to teach it, the only money PADI makes is the certification handling fee. The course is priced by the individual instructor/shop for whatever they think is appropriate, considering their overhead, etc. If the student just wants the course without a certification card, PADI does not get a dime when the student takes the course.

Most of the unusually named courses, like Zombie Apocalypse, are just ways to gather interest in a course that actually teaches worthwhile skills in a fun environment--as that course does. If you get past the title, you will see that the student is actually learning something valuable while taking instruction at a reasonable rate of pay for the instructor/shop.

So why make all these courses PADI-approved Distinctive Specialties? Why not just teach the course without the approval? It's for legal protection. A friend and I collaborated on a workshop with no certification involved, one that worked on good, solid advanced kicking skills (frog kick, modified frog kick, back kick, etc.), buoyancy, and trim. My friend was an attorney, and he consulted with other attorneys after teaching it for a while. He was advised that if there were an accident while doing the workshop and he were sued, he would have to prove to the satisfaction of an untrained jury that what he did in that workshop was within the standards of the dive industry and not some rogue thing that he came up with. By having the course approved as a Distinctive Specialty, he would not have to do that any more. The fact that the largest agency in the world had reviewed the course content and approved it shifted the burden of proof to the plaintiff, and they would find it almost impossible to argue against that approval. So my kicking, buoyancy, and trim workshop is also now a Distinctive Specialty, and for the same reason.

This might actually have been the most interesting and informative post in the entire thread. Thanx @boulderjohn! (-;

 

[lermontov]

4. A couple years ago, in preparation for our trip to Australia, I certified two friends of mine. A few months later, I certified them AOW. A few months later, we were diving in Australia. Our first day doing so was on a day boat, and I was amazed as the DM/instructor assigned to our group (there had to be 100 divers on the boat) essentially reviewed the entire OW class on the way out to the reef. When I took our DM aside afterward and told her I had a different regulator setup (long hose and alternate bungeed around the neck) she said, "Why in the world would you do that?" I showed her the setup, and she was doubtful. She conferred with others who determined it would be OK for me to use it. During the day, all the other instructors came by to check out my bizarre setup. None had ever seen it before or even heard of it. After that day, we got on a liveaboard. We all did a checkout dive, after which we were assigned to groups by perceived ability. My two brand new diving friends and I were the only ones assigned to the group that could dive unsupervised by a DM.

Thinking this through, I think that even today, someone who has achieved the MSD certification might very well be in the top 10% of divers in terms of training and experience.

this is just sad

 

[JamesBon92007]

I only owned aluminum tanks for a brief period, i didn't like the buoyancy swing. So I only dive steel.

Ditto. I dive aluminum on trips 'cause that's what they have usually. Plus I have to rent the BC. You can't even rent a tank backpack at some places.

Aluminum tanks sounded great when they first came out with them.

 

[Diving Dubai]

[QUOTE="dberry, post: 7696843, member: 453191" but I was commenting on the +/- 0.1m while doing a task. A 3" swing in open ocean still seems impressive to me [/QUOTE]

Don't be too impressed. It is as a practical skill, pointless. By that I man not something you can or would ever use. To correct you you can move 10cm up or 10cm down (4") either way - A metric dive computer has the smallest increment of 0.1m. So for instance if my depth should be 10m I can drop to 10.1m or rise to 9.8m.

Now while it's not a practical skill it teaches you 2 things.

1. Breathing around the mid point of your lungs (not the top half)

2. To go slowly and smoothly with your tasks.

My understanding of it all was greatly helped by reading a blog that TS&M posted some time ago.

Like I said the skill has no real use as you have to time your breathing but it does prove an understanding of the techniques you use in normal day to day diving

 

[dberry]

Not entirely pointless... diving on the east coast of Bonaire last week I wanted to get eye-to-eye with a big sea turtle resting on the reef, without touching the reef myself. The guide was (rightfully) very clear about not even 1 finger touching. The photos came out fairly well, but better control would have been nice. Not uber yet

 

[Bob DBF]

I only owned aluminum tanks for a brief period, i didn't like the buoyancy swing. So I only dive steel.

If you dive a steel HP 80 , there is a larger buoyancy swing. The characteristics of the AL80, with it being positive when empty and lighter at the butt is a big PITA. Not to mention carrying the extra weight. I used them for quite a while, and occasionally now, but I certainly prefer steel.


Bob

 

[boulderjohn]

I am confused about the references to buoyancy swings, with AL being compared to steel. The buoyancy swing is created by the loss of the weight of the air that was consumed during the dive. That will be the same regardless of the composition of the tank.

What will be different is how that weight less is distributed. Some tanks get very much butt-light. Others not so much.

Both aluminum tanks and steel tanks have their places, and you should use the ones that best fit your needs. For most all around diving, I prefer steel tanks on my back, and I prefer to carry aluminum. That is mostly because 1) I don't have to carry as much weight and 2) I can usually get more air. But that is not universal. Of the tanks I own, it is roughly a 50/50 split, and I use them all.

 

[boulderjohn]

To give you an idea of what I consider to be lunacy in some places, a dive shop I have used frequently in Florida routinely fills AL 80s past their rated capacity, frequently to nearly 3300. That means they will have roughly 85 cubic feet on average. I bring my own LP steel 85s for fills, and they won't full them to their rated pressure--too dangerous, they feel. They typically stop at 2500. (For those that don't know, that is the opposite of how most shops work--those LP 85s are routinely filled to 3800 in cave country) Thus people renting AL 80s from that shop routinely get more air than I do with my LP 85s.

So when I return next year, I will get my fills elsewhere, even though it will be much less convenient.

 

[JamesBon92007]

If you are comparing an aluminum 80 to a steel 85 then I'm assuming the steel tank weighs more (on dry land weight). But if you are comparing it to a steel 72 then the steel tank weighs less. Also, the capacity of an aluminum 80 is only 77.4 cu/ft at 3000 psi. You need to "overfill" by 10% (3300 psi) in order to get the full 80 cu/ft. The same is true of the old steel 72 tanks--you have to fill them 10% over the rated pressure of 2250 psi to 2475 psi in order to get 72 cu/ft (which is actually closer to 71.2 but can vary a little). There is less difference in buoyancy between a full 72 and an empty 72 than there is with a full aluminum 80 and an empty aluminum 80. I don't know about the steel 85s.

I suspect that some dive shops only fill your 85s to 2475 because that is the maximum fill for the older steel tanks.

 

[TMHeimer]

[QUOTE=" There is less difference in buoyancy between a full 72 and an empty 72 than there is with a full aluminum 80 and an empty aluminum 80.


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Yes. I used to have a steel 72 and found the "buoyancy" to be "better" than my AL80s. I brought up this topic years ago. My reasoning was that even though the loss of weight as you use air is approximately the same, the steel is still a bit negative when near empty, while the AL is positive. If you're properly weighted for each, this shouldn't matter, but it always felt that way to me. I guess it's the buoyancy of the bottom of the AL that creates the different feeling when near empty? That's what I was told anyway. Once I really knew what was going on, it really didn't make any difference to me which I dived.