NDL

[JeffAustin]

...your brain, or your wrist computer. If you are relying on your computer to tell you what to do, then you probably don't have confidence in your own skills regarding profiles and dive planning. Nobody is born knowing this stuff, but the longer you spend depending on your computer, the harder it will be to wean yourself from it. Diving is much more pleasant when you and your buddy know your plan before hitting the water. Diving a plan empowers you as a diver, puts you in control. Diving a computer puts you in the back seat, a passenger on your own dive. "Are we there yet??"

I agree with UP regarding the NDL line. It's like running to the edge of a cliff blindfolded, and not really knowing where the edge is!

 

[wreckchick]

I trust my brain to know if my computer is acting completely out of line, but I trust the calculations in the computer better than I do the ones in my head, on the fly. Having a computer doesn't give anyone an excuse for not having a plan. No one seems to think that using the tables and doing hand calculations is using a crutch when a computer is. The computer is a faster, more efficient set of tables.

Honestly, why would I want to wean myself from the computer? Why couldn't I use it forever and ever? It's not a sign of weakness to use the most efficient tool for the job. I don't see people still using an abacus because a calculator is some new fangled thang not to be trusted!

R

 

[O-ring]

biscuit7 once bubbled...
I trust my brain to know if my computer is acting completely out of line, but I trust the calculations in the computer better than I do the ones in my head, on the fly. Having a computer doesn't give anyone an excuse for not having a plan. No one seems to think that using the tables and doing hand calculations is using a crutch when a computer is. The computer is a faster, more efficient set of tables.

Honestly, why would I want to wean myself from the computer? Why couldn't I use it forever and ever? It's not a sign of weakness to use the most efficient tool for the job. I don't see people still using an abacus because a calculator is some new fangled thang not to be trusted!

R

...at some point computers become less than optimal depending on the type of diving you are doing. You may not like it forever and ever!

 

[Raven C]

O-ring once bubbled...

...at some point computers become less than optimal depending on the type of diving you are doing. You may not like it forever and ever!

The true voice of reason. R

 

[JeffAustin]

when your computer is "out of line". Would you know it? What if your computer doesn't agree with someone elses? Who's do you trust?? You've done one dive, and now your computer isn't working right; do you blow off your second dive because you really don't have a clue how long you can stay down at 70 ft. and still be safe?

You are buying into the myth that a computer is smarter than you. Hey, if that works for you, if you believe that, then I guess you should be depending on a computer after all, because it doesn't sound like you trust your own instincts.

It is a sign of weakness to use and depend on dive computers, because with experience your mind is the most efficient tool for the job.

 

[MikeS]

JeffAustin once bubbled...
...your brain, or your wrist computer. If you are relying on your computer to tell you what to do, then you probably don't have confidence in your own skills regarding profiles and dive planning.

The answer to this question depends on the context, and it’s not an all or nothing proposition as you make it sound. Your question is the equivalent of asking which do you trust more, your table, SPG, pressure gauge, and bottom timer, or your brain.

If you’re relying on your computer to tell you what to do you’re in trouble, since the computer doesn’t tell you what to do, at least mine doesn’t. What it does is provide you information upon which to base your decisions just as a table, SPG, pressure gauge, and bottom timer do. However, the computer has the benefit of being capable of calculating the remaining NDL time and estimated airtime based on the current depth, near real-time without human error.

JeffAustin once bubbled...
.. Diving is much more pleasant when you and your buddy know your plan before hitting the water. Diving a plan empowers you as a diver, puts you in control.

This is true whether diving with a computer or table, SPG, pressure gauge, and bottom timer. Diving with a computer doesn’t mitigate the need for a dive plan. To the best of my knowledge, there isn’t a dive computer out there that calculates turn points or Rock bottom.

JeffAustin once bubbled...
... Diving a computer puts you in the back seat, a passenger on your own dive. "Are we there yet??"

You make it sound as if the computer some how directs you around and runs the dive for you. This is not true with any computer I’ve seen. Your statement leads me to believe that you’ve never dived with a computer or are grossly exaggerating to further your agenda (not meant as a flame and/or insult, simply an observation, no offense intended).

JeffAustin once bubbled...
... I agree with UP regarding the NDL line. It's like running to the edge of a cliff blindfolded, and not really knowing where the edge is!

I agree with both of you. With over 100 open water dives on my Cobra it has never yet been in Deco mode. I hope it never is because that would mean my dive plan was totally blown.

Mike

 

[wreckchick]

JeffAustin once bubbled...
when your computer is "out of line". Would you know it? What if your computer doesn't agree with someone elses? Who's do you trust?? You've done one dive, and now your computer isn't working right; do you blow off your second dive because you really don't have a clue how long you can stay down at 70 ft. and still be safe?

You are buying into the myth that a computer is smarter than you. Hey, if that works for you, if you believe that, then I guess you should be depending on a computer after all, because it doesn't sound like you trust your own instincts.

It is a sign of weakness to use and depend on dive computers, because with experience your mind is the most efficient tool for the job.

If my computer is a couple minutes off, I might not notice, but since I don't dive the computer to the edge this presents no issue what so ever. When you are diving with a buddy that has a computer, the most conservative wins just like you only dive to the experience level of the least experienced diver. It's a safety margin. If the computers are grossly out of whack, it won't be hard to figure out which one makes sense and which is acting up.

The speed at which a computer can do the calculations necessary to give me real time information about my estimated remaining NDL at any given depth far exceeds that of my brain. I use a computer as a TOOL to enhance my diving experience and to help myself SAFELY build up more experience.

It is a sign of weakness to not see the value of a tool that can greatly aid a diver in making safe, repetative dives for several days in a row.

Any tool can be misused, that includes a computer. Used properly and within the person's training and limits, there is no reason not to use one. When someone uses a computer to bail themselves out of trouble they have put him/herself in that is a misuse of the tool. It is NOT the tool's fault.

R

 

[JeffAustin]

If you are looking at your computer during the dive to find out how much NDL time you have left , what are you doing?? You are changing your plans underwater based on "up to date" new info you are seeing on your wrist (being a passenger). That is different than having a plan in your mind that you stick to throughout your dive. I have no "agenda' as you put it, beyond wondering why people don't trust their own brains, you know, they work really good at multi tasking and figuring stuff out, if you let them.

I dive a Vytec, in gauge mode.

How do you figure this on the fly info helps you when you are diving as a team, whose computer do you trust? I'm not going to change my plan because my buddies computer just told him he's got an extra five minites of NDL, would you?

It's a bad idea to change dive plans underwater, and following a computers NDL and air consumption estimates leads divers to do this very thing.

 

[MikeS]

JeffAustin once bubbled...
If you are looking at your computer during the dive to find out how much NDL time you have left , what are you doing?? You are changing your plans underwater based on "up to date" new info you are seeing on your wrist (being a passenger).

This is true and one of the major advantages of a computer in that it let’s you do so. But looking at the speedometer rather than using a stopwatch and mile markers to tell how fast your going doesn’t make you a passenger.

JeffAustin once bubbled...
How do you figure this on the fly info helps you when you are diving as a team, whose computer do you trust? I'm not going to change my plan because my buddies computer just told him he's got an extra five minites of NDL, would you?

When diving as a team whose bottom timer do you trust? The answer is the same to both questions, the more conservative of the two.

JeffAustin once bubbled...
It's a bad idea to change dive plans underwater, and following a computers NDL and air consumption estimates leads divers to do this very thing.

I agree that relying solely on a remaining air time estimate is inappropriate, as it does not incorporate the concept of turn pressures or rock bottom for ascent or even the effect of work load on remaining air time. However, it can be a useful tool to double-check that you’re following the plan.

The key to a computer or alternately tables, SPG, depth gauge, and bottom timer, is understanding how they work and using the information they provide to make good decisions. The problem is not computers, but in thinking that you don’t have to think because, you have a computer. But this is true in any context. How many divers have you seen jump off the boat with a plan to let the DM know when they’re down to 1,000 psi armed with PADI dive planning knowledge (be back on the boat with 500 psi)?

Mike

 

[UGA]

Jeff,

If you're diving a VyTec in gauge mode, can I trade you my Vyper?

I understand paying attention to dive limits independently of a computer, and I can understand some people no wanting to use a computer, but why would you use a Vytec in gauge mode when a unit probably $800 cheaper would do the same thing (as a gauge)?