How to achieve good and proper Trim while diving

[The Chairman]

is not natural

Scuba isn't natural. Not at all. Why would you think going horizontal would be any more natural? But cavers can do it.

Pete I think your crusade toward the non-horizontal divers and not experienced divers is affecting your judgement.

Crusade? All of ScubaBoard is about making better divers of us all. Why would you see this as a bad thing? However, teaching OW divers to be neutral has affected my judgement in that I no longer believe as you do. I used to, but then I saw a better way to teach. No kneeling. No lying on the bottom. No standing either. Always, always horizontal, except after the safety stop. It's my heartfelt belief that most divers come out of their OW with a distinct lack of control. They have to resort to kneeling to accomplish the most mundane tasks like clearing their mask and they kick with their fins at a thirty-degree angle, just like their instructors. Is it bad? As much as they hurt the reef or freak out: yes. Certainly. My aim is to produce divers with superior to trim, propulsion and buoyancy. My students do everything horizontally while on Scuba, or they just don't pass. Clear their mask, R&R their BC, share air... EVERYTHING. You call it a crusade and I call it a way of life and teaching. Teach and let teach.

So, we obviously disagree on many subjects. You think you're right, while I know I am! Dive and let dive. Reiterating the same points over and over won't win me over. Just saying you've made an assertion only proves that you've made the assertion. You still haven't convinced me that you're right and I'll probably never convince you. But maybe I'll convince the next diver that comes along to adopt this "crusade" I'm on and they'll learn to get horizontal and in control all by themselves. Then they'll understand why and then they and the reefs they dive on will be safer. Dive and let dive!

but I'm not sure how this would affect or change the above considerations.

It was shot all in the Scuba Position. That was my point. You said it couldn't be done, and here's my proof to the contrary. It's my firm belief that getting horizontal improves any Scuba experience. I also believe that you're not in total control until you are horizontal. You don't have to dive "my way", but I'm going to. Don't hate because I've gone all horizontal! I've might have said this before but, Dive and let Dive!

 

[npole]

I feel we're talking about two different things.. you're talking about how a new divers should learn how to be neutrally buoyant and how to use the correct posture; while I'm talking about a diver that evolved into making his dive efficient for a task.
Saying that you must be horizontally, no matter what, is a very limited vision of the dive techniques: there's reasons of why you won't be horizontal, and it's not about what about I think, it's about the human body.. I mean there's a reason of why most people uses their hands to type on a keyboard, surely you can use your nose as well, it's not impossible, but it isn't either optimal.
At the same way you can shoot your videos while being perfectly horizontally, and in certain circumstances you're forced to do (you said that I have claimed to be impossible... while I actually write the opposite!), but it couldn't be efficient.
I believe you think that I'm trying to convince people to not dive horizontally (doh!)... while I have replied to whoever have asked (see my first post in this thread) if there's a reason of why you WON'T (intentionally) not dive in that position, and yes there's reason of why you won't INTENTIONALLY move around while not being horizontally because in that circumstance is the most efficient way to perform that specific task. I mean isn't even an opinion, it's about human muscles, unless you're made or rubber.

 

[The Chairman]

you're talking about how a new divers should learn how to be neutrally buoyant and how to use the correct posture;

Sure. We're in basic scuba. Why wouldn't I encourage that here?

while I'm talking about a diver that evolved into making his dive efficient for a task.

Probably not a "basic" subject. However, you have yet to show how being at 30 degrees is 'more efficient'. Just saying it, doesn't make it so. Physics teaches us that a 30-degree angle is incredibly inefficient when propelling anything. That means that 33% of your thrust is downward, with only 66% pushing the mass forward. I would rather have a 100% of my thrust pushing the object. You'll need to overweight yourself to keep from floating up and once you stop kicking, you're sunk. Literally, you'll sink unless you add air to your BC. Once you start moving again, a third of your thrust will be pushing you to the surface, so you'll have to vent that air you just put in. Read my article on vectors. Physics doesn't lie. All the professional photographers I have seen make their cameras nigh on to neutral so they won't have to work hard. There's no supporting of weight when the camera is neutral so there's just no need for the angle. No, I just don't get it and I do disagree with your premise. Again, just because you've always 'done it that way' doesn't make it efficient.

I mean isn't even an opinion, it's about human muscles, unless you're made or rubber.

Maybe you should come dive with me and see how I do before you tell me how I can't do it.

 

[MichaelMc]

Camera toting divers are their own case... (however it works out), not an issue for most divers....

I'm horizontal 90+% of the dive. Why wouldn't I be. It's my lying on the bed looking about pose. Exceptions are near the surface, if I screw up on ascent, or some specific reason like looking under a ledge etc.

It's a way easier way to dive! Imagine lying on your stomach on the bed watching a movie, legs up just because..., no neck strain because your head is mostly weightless. Turning your head to look about, sometimes rolling a bit to look at something. Can you conceive of an easier way to cruise about, not constantly changing from vertical while still, to horizontal when moving. It is way easier.

And as a rec diver, there's no reason you need to keep leg skulling to stay horizontal when still. It is not hard to shift some of your weights around (typically headward) so you balance out as level. Tank band pockets is one way, or a BP/W. Assuming you're not playing with adding and removing stages there should be no need to skull with your legs to get level. And stages are not an issue for most divers.

 

[npole]

However, you have yet to show how being at 30 degrees is 'more efficient'.

It's more efficient for the specific task, because with your arms you'll cover a much bigger area efficiently. Efficient isn't just being hydrodynamic, but performing the task in the best possible way. It's always a compromise.

Just saying it, doesn't make it so. Physics teaches us that a 30-degree angle is incredibly inefficient when propelling anything. That means that 33% of your thrust is downward, with only 66% pushing the mass forward. I would rather have a 100% of my thrust pushing the object. You'll need to overweight yourself to keep from floating up and once you stop kicking, you're sunk. Literally, you'll sink unless you add air to your BC. Once you start moving again, a third of your thrust will be pushing you to the surface, so you'll have to vent that air you just put in. Read my article on vectors. Physics doesn't lie.

I already explained why being tilted while operating a photo/video gear is better than being completely horizontally (see my previous messages)... but give a look at the end of this reply.

All the professional photographers I have seen make their cameras nigh on to neutral so they won't have to work hard. There's no supporting of weight when the camera is neutral so there's just no need for the angle. No, I just don't get it and I do disagree with your premise. Again, just because you've always 'done it that way' doesn't make it efficient.

You're mixing the weight of the camera (and btw having the camera neutral doesn't mean eliminating its mass) with its movement.

Maybe you should come dive with me and see how I do before you tell me how I can't do it.

You're again mentioning phrases that I never wrote in my posts. I never said that you can't do it, as I never said that you can't write your reply by using your nose.

This will explain the whole thing better (excuse me for my poor painting skills):

While being horizontally (picture on the left) you will cover a much smaller area that is concentrated below the diver (note that the apparent area is indeed identical, but after reaching the perpendicularity you gonna have your camera upside down, so that part will excluded from the normal working area). To film a subject in front of you, you will put your arm under stress, because to operate the camera you have to raise your arms towards your head, after a certain angle you have to tilt your whole body (coincidentally assuming the position on the right). Unless you're always filming stuff below you, you will accumulate fatigue in your arms (that doesn't depend by the weight of your camera, assuming it's neutral, but because of the muscles stretched along your body and arms).

On the right you see the position of a "common" videographer: it's far to be hydrodynamic, because you're exposing a larger portion of your body toward the mass of water. But the arms will be in a "natural" position to cover a larger area around you in a more efficient way, both in front of you and to your sides.

The first position is ideal to travel, and we are all using it (I mean there isn't even needed to comment it.. it's a fact); while the second position is ideal for filming.
In certain cases you'll be "forced" to use the first position while filming (I imagine in a cave or when you're near to the bottom and you won't risk to raise suspension or such or when there's current and you're forced to trade the comfort with the hydrodynamics) so it's definitely possible to film while in that position (hell... I can film with the camera on my back or while upside down!) ..but ideally you want to be in a much comfortable position for a smoother video (especially if you have to follow a subject longer than few seconds).

To resume (excuse me for the wall of text): there's ins't THE universally correct diving position, there's the position that is more comfortable for a given task. Now, if you aren't operating a camera and you're tilted like a sea horse, while scraping the bottom and agitating your hands like a puppy... you're surely doing something wrong, but that's another matter. I'm just saying that force yourself to be always horizontally, no matter what, is IMO a nonsense.

After this I think I would end here, because it's like circling endless.

 

[The Chairman]

there's ins't THE universally correct diving position

Again, we completely disagree. Your "wall of text" contains a number of suppositions which fly in the face of simple vector physics. The best position for 95% of your diving, ie the Scuba Position, is not kneeling, it's not standing, it's not even at a 30-degree cant, but flat, flat, flat. Do you change that position momentarily to look at a fish or to pick up sunken treasure? Sure. But the most efficient way to move through water is horizontally where you minimize drag and maximise your thrust vector. The best way to avoid stirring up silt is with your feet slightly above you, but kicking straight back. Now, I see people using your 30-degree cant all the time and it's hard to teach them to horizontal once the perfect this bad habit. They don't even need a camera to get there, but once they have a camera they are still in that same attitude. I also see people swatting at flies underwater too, but that doesn't make it right or efficient. Those people are squandering a ton of air trying to correct their attitude to keep themselves at that thirty-degree cant, because no one has taught them the basic Scuba position. There's a better and more efficient way to dive that won't silt out the place, provides maximum control of your depth and will allow you to get superior footage. You can call that anything you want, but my term is the Scuba Position.

After this I think I would end here, because it's like circling endless.

Yes, yes you are. But hey, Dive and let Dive. I'm going to continue to get my students flat, flat, flat.

 

[seeker242]

but want to know how much time during any dive a seasoned diver spends in this position.

My instructor never breaks trim, so pretty much 100% .