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Discussion Starter #1
Hello,
Having recently watched a couple of videos on youtube (most notably: dsmb deployment by Clare) I wondered about one thing:
How is it possible that a diver hovers exactly at a given depth, without moving up/down?

I know it might sound like a very silly question, but... I am serious!:).

I mean, albeit seriously doubtful, at the end of the day I suppose that these divers do breathe ;). And as we all know - breathing adds gas to lungs, increasing the overall buoyancy of our body. Then Archimedes comes and takes us up.

Staying at the same depth *generally* is not extremely difficult (at least in principle, in calm waters etc. :]). But staying at the same depth without ANY movements up/down is a totally new story...

So... how to become a friend with Archimedes? Shallow breathing? Quick breathing? But it is always said that deep, slow breathing is the key...

I would also allow myself to ask you - when you are adjusting your buoyancy - what is the stage (as far as breathing is concerned) when you want to be neutrally buoyant and do you make equal (timewise) inhale and exhale? Personally I have found neutral buoyancy at "half full lungs" to be the best solution - as it means that I am positively buoyant for the same amount of time as negatively...

You know... I don't have PhD in Physics but something tells me that hovering without any movement up/down *whatsoever* is just plain cheating! ;)

Best,
Theriel
 

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It took me 50 dives to be able to hover perfectly still, and to be able to 'corkscrew' through the water. I remember both days vividly because it meant so much to me, to have overcome a personal diving hurdle. Now, I have no problem with completely still hovers, which aids your photography a great deal.

Maybe do a PPB (Perfect Buoyancy) course to 'fine tune' your breathing and movements in the water. Or if you have the opportunity to play in a pool, use a spare weight belt, about 4 kg, place it on the pool bottom, swim towards it, pick it up, alter your BC buoyancy and breathing to compensate for the added weight, then swim along before putting it down again without altering your position in the water.

This is a great exercise for understanding how buoyancy works and how just those small movements or small breaths make a huge difference.
 

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Bashing head against brick wall
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Just one observation. You'd find it impossible to adjust for an extra 5kgs using just your lungs. PADI suggest the use of a lift bag for objects weighing over 4kg for their Search and Recovery course for fairly obvious reasons. You accidentally drop something that weight and you run a substantial risk of rocketing to the surface.
 

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I've been through fundies, Tech1 and Tech2, done god knows how many hundreds of training and real dives to practice it, and am still working on it.

These are the following tricks I've picked up

1. Practice, and a lot of it, constantly practice - a lot of it with no visual reference so you don't stay dependant on being able to see something.
2. Absolute perftect weighting. The closer you can get to this, the easier control becomes
3. Relaxation - calm, slow breathing, calm, slow movements
4. Stable, Horizontal trim - no pockets of gas moving around
5. If you have to adjust with gas, make micro changes rather than macros changes
6. Aim to be perfectly neutral at the mid point of your breathing cycle.

Get all of this right and the ony gas to manage is the very small amount of gas in your wing - which is irrelevent because you are not changing depth, and then gas in yoru lungs. The gas in your lungs would be enough to make you ascend or descend if you held it, but you don't - just keep breathing. Get it right and you should be able to hold stops more precisely than your computer can actually measure. then you know you're getting there.
 

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700 dives, and GUE-F, and I'm still working on it :)

practice, practice and more practice. The key I found was that small (normal - as if i was sitting on the sofa) breaths helps.
 

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I don't really know how I do it :D

In all honesty, you have to just do massive amounts of practice, basically going diving again and again for as many times as you can as long as you can.

Then one day it clicks.

Be warned though, if you do a season where you only manage about 20 dives, it will unclick.

I am now back to trying to get it to click again.

Digs.
 

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Just hold your breath... :D then breathe out fast and hold it again before you sink :D
You jest but this is exactly what I used to do. Still do sometimes if I am not thinking about it.

Before fundies I had mastered the art of being still and neutral but it wasn't in the middle of my breathing. I don't know why but I got into the habit of holding my breathe in and when I breathed out I would sink and so breathe in again to hold it. I learn't on fundies to put a bit more gas in the wing and how to breathe out all the way to stop myself from going up or if I want to sink a bit. It is just practice but first you have to understand how it works.
 

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Just hold your breath... :D then breathe out fast and hold it again before you sink :D
Of course, you may want to breath in at some point ............. that will help stop you sinking :wink:
 

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Jesus don't want me for a sunbeam
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don't worry about it, sink like a stone, crawl around the bottom and winch yourself up the shot/DSMB.
Nothing wrong with that :D Perfect buoyancy isn't much use on a lot of the wrecks I dive, last thing you want to be in a current is neutral.
 

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All hail the mighty ZOM
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No - that's winch yourself up someone else's shot isn't it?
Sort of. Most of the divers I saw as I was hovering, demi-god-like just off the line on the 5m safety stop had the grace and buoyancy control of a safe chucked off Swanage Pier, hanging vertically down off a fist gripping the mooring line.
 

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No wonder the Thistlegorm is in such a bad state :(
 

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The smell of freshly turned delrin is more powerfu
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1. Practice, and a lot of it, constantly practice - a lot of it with no visual reference so you don't stay dependant on being able to see something.
2. Absolute perftect weighting. The closer you can get to this, the easier control becomes
3. Relaxation - calm, slow breathing, calm, slow movements
4. Stable, Horizontal trim - no pockets of gas moving around
5. If you have to adjust with gas, make micro changes rather than macros changes
6. Aim to be perfectly neutral at the mid point of your breathing cycle.
sigh.. Garf wrong again :)

1) your going to have to start with a visual reference otherwise your not going to know where you are.. Good plan might be to start with something
Like garf or clare but if their unavalible your reel/spool hanging at 6 meters seems to be there with you a lot of the time. Its even a good way to kill time on deco :)
 

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All hail the mighty ZOM
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sigh.. Garf wrong again :)

1) your going to have to start with a visual reference otherwise your not going to know where you are.. Good plan might be to start with something
Like garf or clare but if their unavalible your reel/spool hanging at 6 meters seems to be there with you a lot of the time. Its even a good way to kill time on deco :)
You don't even need that. Little bits of crap in the water are just as good. But you go bos-eyed.
 

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The smell of freshly turned delrin is more powerfu
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You don't even need that. Little bits of crap in the water are just as good. But you go bos-eyed.
agreed :)
 
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