Teaching Computers in OW class vs tables

[Web Monkey]

Well, actually I took the computer out of the bag and straped it on. If I did something to change the mode (of which there is no display telling you that) then I was somehow able to do it by?...I have no clue. You have to go through a couple of nested menues by touching electrical contacts to do it on purpose.

Although I don't know which computer you use, or it's default settings, speaking from a software perspective, the default settings are typically the most conservative/least dangerous.

If the user wants more aggressive settings, that would be their configuration choice.

Terry

 

[Web Monkey]

It's a reasonable response, since the condition of your body would then be outside the parameters that the algorithm in the the computer can handle. Your body is in a condition where the computer can't safe dive conditions, so it locks out.

Some computers will lock you our for going too deep. Some for too long. You might think it's reasonable but I don't need it.

ok so it's better they just stop telling you anything?

They stop working after you've surfaced, in an attempt to stop you from diving again in what the computer has calculated as a dangerous condition.

I disagree with this. It's not fact. They don't monitor the divers condition at all. They simply take depth and time and run it through some equations. At that, most are using models that many of us feel are obsolete and wouldn't dream of actually using. There just now starting to slowly impliment some of the stuff that divers have been doing for years.

Although the computer doesn't directly monitor the diver, the newer air integrated computers model various tissues of an average diver and apply known data (time, temp, depth, %O2, breating rate and volume consumed).

Although it doesn't know what's happening inside any specific person, it does know that the user has violated whatever manditory stops there were and is attempting to prevent the user from diving again.

Except that if you're using the computer as your primary source of decompression information you'll be lost on the next dive if you try to do it with a depth gauge and a watch.

Why lost? If you're willing to take the risk, you can always manually calculate your last profile, then dive the tables using whatever group you come up with.

Personally, I'd bag diving for the rest of the day and start over tomorrow.

Like I say, I used to use one until I realized that I just didn't need it.

There aren't any SCUBA police, You're free to plan your dives using any method you like.

Terry

 

[MikeFerrara]

Although I don't know which computer you use, or it's default settings, speaking from a software perspective, the default settings are typically the most conservative/least dangerous.

If the user wants more aggressive settings, that would be their configuration choice.

Terry

The setting that caused the problem was not the default setting nor was it one that I ever purposly changed.

It's also not a setting that reverts back to a default after it sits a while.

Most conserervative as far as decompression doesn't always mean less dangerous. If I hadn't already had my ascent planned and believed the crazy thing I would have believed that I NEEDED to stay at depth. In this case staying at depth means in a cave. Luckily I knew better because I was cold due to a leaky dry suit.

 

[MikeFerrara]

They stop working after you've surfaced, in an attempt to stop you from diving again in what the computer has calculated as a dangerous condition.

Why would you want help. The only good thing I have to say about the last computer I used on a regular basis is that it was one that won't lock up for any reason.

Although the computer doesn't directly monitor the diver, the newer air integrated computers model various tissues of an average diver and apply known data (time, temp, depth, %O2, breating rate and volume consumed).

Usually using obsolete models with no prior knowledge of how I've felt after similar dives.

Although it doesn't know what's happening inside any specific person, it does know that the user has violated whatever manditory stops there were and is attempting to prevent the user from diving again.

It's not a matter of what the computer does if you skip stops. It's a matter of how the computer may penalize you for an ascent that's better.

Why lost? If you're willing to take the risk, you can always manually calculate your last profile, then dive the tables using whatever group you come up with.

Now you're getting it. If you can manually calculate your last dive then you have little use for the computer.

However if you're unable to do that you have to stop diving.

Personally, I'd bag diving for the rest of the day and start over tomorrow.

See?

There aren't any SCUBA police, You're free to plan your dives using any method you like.

Terry

Of course and so can you. I of course couldn't care less if you or any one else uses a computer. I've baught plenty of them before I figured out that I didn't need one and it in fact was a hinderance in that the information that's most useful...depth and time...is often stuck off in a corner in tiny numbers to make room for a large display of NDL which I don't really care about.

As you say there aren't any scuba police (well there are on some dive boats) so you can follow your computer all you want and stop diving when it blinks the wrong color.

 

[Web Monkey]

It's not a matter of what the computer does if you skip stops. It's a matter of how the computer may penalize you for an ascent that's better.

Now you're getting it. If you can manually calculate your last dive then you have little use for the computer.

However if you're unable to do that you have to stop diving.

See?

I've only used one computer (my Smart-Com), and so far, it hasn't penalized me for anything, or ever locked me out, or told me to stop diving when I thought I should be able to.

I suppose if it started causing problem, I'd have to decide if it was right, or I was right, and act accordingly.

FWIW, I also dive with a watch, analog depth gauge, and an analog SPG with the same quick disconnect as my computer, so if something bugs out, the changeover is easy.

Also, since I deal with technology all the time, I like the idea of having a manual analog backup. If something computerized is bugging out, I don't want to replace it with another computer.

Terry

 

[getwet2]

But how does the computer apply conservatism? We don't just shorten or lengthen the NDL we reshape the whole ascent curve.

I'm not an expert on algorithm's but by changing the conservatism setting on the unit it is telling the unit to use the algorithm differently. It will change how the unit calculates the information.

I guess it's the same as planning your dive using tables but you plan them using greater depths then what you are actually going to dive or by going to a higher letter group then you actually are.

 

[MikeFerrara]

FWIW, I also dive with a watch, analog depth gauge, and an analog SPG with the same quick disconnect as my computer, so if something bugs out, the changeover is easy.

Also, since I deal with technology all the time, I like the idea of having a manual analog backup. If something computerized is bugging out, I don't want to replace it with another computer.

Terry

I dive with a bottom timer and an analog watch with a moveable bezil.

I get as much divetime as I want, haven't been bent yet, the watch set me back about $30 and the bottom timer about $120.

The only problem is the pile of computers that I have and don't use that cost me a lot more. LOL

 

[kalvyn]

That's not very a very comforting statement, considering the dives we'll be doing together on Sunday ...

I think I need a tech writer to help me with my legal disclaimer. What do you think?

Jimmie

 

[jviehe]

First of all stats have shown that divers who solely dive by computers have had a higher occurrence of DCI than table divers.

Which stats, and was it statistically significant?

 

[MikeFerrara]

Which stats, and was it statistically significant?

None of the statistics in diving are significant because there are so many variables.

By looking at DAN data and watching divers in the water though you can get some idea of what's going on.

A large percentage of the divers who get hurt have little recent experience, little training and poor skills.

Many of the divers who get bent seem to be vacation divers doing lots of dives in a short period of time, following a computer, staying up late, drinking and flying home when it's all over.

Over and over we hear these incedents called undeserved hits. Now it's not the fault of the computer exactly but how often do we hear..."My computer was in the Green"? LOL

But then again when the big number in the middle is NDL with stupid color bands to indicate decompression status, I think the computers were designed to be used just exactly that way...with no thought at all. They certainly seem designed for use by a vacation diver who doesn't want to think or be bothered with the details.

I don't use one because I don't need one but if I did want one I'm not aware of any that I would like. I don't care about pretty bands of color or NDL. I would want depth and time to the most prominant part of the display. If I go past the magical "NDL" I don't want it to display a "total time for ascent" and a ceiling. I want it to display a recommended schedule based on the gasses I told it I was going to use.

One of the most popular tech computers displays like 3 days of decompression until you actually switch gasses so unless you know what your decompression is going to be ahead of time anyway you're pretty much in the dark. Of course if you know what it is anyway then what do you need the computer for? LOL