Holding depth in Water column??

[mark01]

Ok, how do you folks manage to hold depth when

A. There is very little "floaty" stuff in the water and
B. You cannot, for whatever reason, use your buddy for a reference point, and
C. You cannot see the bottom or any other reference point.

The basis for the question is that I did a nav cert course today and with the DM behind me, and with no, (or very few) "floaties" in the water, and not being able to see the bottom, my depth oscillated all over the place (+/- 8 feet). Obviously, good bouyancy is necessary, and at this point in my skill building I can get neutral and hold it when I have visual cues, but absent those cues, I apparently suck. I was watching my depth gauge as I was watching the compass heading, but obviously that wasn't enough because once I began oscillating, each one amplified the next...maybe I was just way too anxious about wanting to do well..

I do know that performance anxiety played a part in my troubles, but even when I practiced on my own, I had the same issue going on.

TIA
Mark

 

[Jasonmh]

A great question! Hope you get some good answers.
Personally, I have my depth gauge on my wrist, where it is in my field of view as I am swimming (I see that you also were looking at yours while swimming). There are also smaller clues, like changing pressure in the ears. There can also be (depending on the conditions, site etc.) changes in ambient light or water temp.
Performance anxiety can certainly divert your attention and concentration from your depth. Keep practicing, and when you see your depth get off by more than a few feet, correct as you are swimming.

Edit- One more thing. Changes in breathing can greatly affect a change in depth. Once neutral and horizontal, concentrate on slow, full, and steady breaths. It should provide some help in keeping that up/down pendulum of bouyancy changes from starting. Hope that helps.

 

[Doc]

Buy a depth gauge, stare at it.

I say this only half in jest.

It's lesson #4....

It's what I call, "Fly the plane". Then the next instrument is the compass. If you can maintain depth with gauges, then you follow the compass. Like they teach instrument flying on planes. You can't see anything else. Keeping it "in view" as Jasonmh advises will come along quickly.

The rest is all pretty fish.

btw- 4ft + or - would be a better preliminary goal.

 

[yyidus]

Obviously the best way is the 'depth gauge/computer'. If I'm ascending a little fast I tend to notice it with my ears. But it's hard to notice if I'm only ascending at 10ft/min....

One 'trick' mentioned in night diving is to pay attention to the bubbles your breath out. Over time you can tell approximately how fast they should be rising (and if nothing else.. never rise faster than the bubbles . Again, it won't give you perfection, but absent a gauge, visual cues, physical cues, and a bottom, that's pretty much all you'll have.

I guess one other possible 'trick' is to take something you know to be neutrally buoyant, and let it float in front of you...

I guess my question is: "why can't you use a computer/depth gauge" ?

 

[dumpsterDiver]

If the water is super clear and has no floaties then change in ambient light (and I expect temp) is not going to help much. Looking at the surface can help. Using your ears can help. One of the best tools, (I used to use), is the feeling of a well fitted jacket BC. When you start to go up, you can sometimes feel the bc squeeze you a little. You can NOT use your bubbles because they are behind you when swimming.

When playin these types of "games" it probably helps to try to breath shallow. Small changes in lung volume. If I have to hold my depth in clear water for deco, I usually run a surface marker float on a string. That makes it easy. Also if you just have to hang at one depth (and not move) then looking up at the surface works pretty well (especially if you don't try to maintain a perfectly horizontal trim on deco).

When you throw in swimming, it makes it much harder because you end up swimming up or down without knowing it rather than just trying to maintain neutral bouyancy.

Who needs to swim in open water with zero visual or tactile references for extended periods anyway? If you have to do it, like trying to swim back to the anchored boat while following a compass heading, it is easier to do it at a little more depth like 30 feet than at 10 feet.

 

[scubadiver888]

Ok, how do you folks manage to hold depth when

A. There is very little "floaty" stuff in the water and
B. You cannot, for whatever reason, use your buddy for a reference point, and
C. You cannot see the bottom or any other reference point.

The basis for the question is that I did a nav cert course today and with the DM behind me, and with no, (or very few) "floaties" in the water, and not being able to see the bottom, my depth oscillated all over the place (+/- 8 feet). Obviously, good bouyancy is necessary, and at this point in my skill building I can get neutral and hold it when I have visual cues, but absent those cues, I apparently suck. I was watching my depth gauge as I was watching the compass heading, but obviously that wasn't enough because once I began oscillating, each one amplified the next...maybe I was just way too anxious about wanting to do well..

I do know that performance anxiety played a part in my troubles, but even when I practiced on my own, I had the same issue going on.

TIA
Mark

I'm not great at this yet but I can usually stay within a few feet.

What I do is get neutrally bouyant then just focus on controlling my position in the water, while going along the bottom, using my breathe. As I'm swimming along I'll try to get closer and closer to the bottom then I'll go over things (a barrel sponge or a reef) just by using my breathe. That is, if I don't exhale quite as quickly I'll start to rise. If I let all the air out of my lungs I'll start to drop. With a little practice I get a feel for how quickly I need to breathe to go up, go down or stay neutral.

It was only once I got good at doing this while on the bottom that I got better when doing it without the bottom as a reference.

 

[Thalassamania]

Depth gauge and ears. There are situations in which it can be quite disorienting, especially with crystal clear water (e.g., open ocean). There we use a series of tether ropes for orientation and safety (Haddock and Heine, Scientific Blue-Water Diving, Cal Sea Grant 2005).

 

[1_T_Submariner]

I'm not sure if it is for everyone but, In my opinion this is a difficult skill. I did a class where we did a dive vision obstructed and I had no clue what by depth was unless I was hitting the bottom or my head came out of the water. To me vision is my most valuable tool in maintaing depth.
Ears work pretty good some people better than others and it depends on the depth change.

The easiest way is using a Gauge/computer.

When doing precise navigation counting kicks maintianing direction and depth are a lot of tasks all at once especially with no visual reference. You may want to split these tasks up within your team.

 

[don Francisco]

It's like a pilot flying in a cloud. You have to be able to use your instruments. For managing depth, I rely on my analog depth gauge. The information is a little more "visual" than the digital data from my computer, and there isn't any time lag in showing depth changes.

 

[BarryNL]

It's like a pilot flying in a cloud. You have to be able to use your instruments. For managing depth, I rely on my analog depth gauge. The information is a little more "visual" than the digital data from my computer, and there isn't any time lag in showing depth changes.

Yeah - analog depth gauges are a lot better for this than digital ones. However, there is probably enough debris in the water if you look carefully. Even in the Mexican cenotes I found more than enough floaties to hold depth when needed.