Another Tables vs. Computers Thread

[BHB ScubaTroll]

d'oh

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Scan down the left hand panel to "Group Memberships"
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That will get you into the entire area

 

[minnesota01r6]

It is decidedly not worth the effort to do that.

 

[BHB ScubaTroll]

It is decidedly not worth the effort to do that.

If you don't want to be a member of the same area where MOF/NMOF is located.... that's your business

 

[minnesota01r6]

no, I meant your new thread. By all means, sign up for the SI forum for other reasons, just not for your table on forehead thread. It was...how do I put this....un-funny. Your pun was so bad it didn't even make me groan.

 

[BHB ScubaTroll]

no, I meant your new thread. By all means, sign up for the SI forum for other reasons, just not for your table on forehead thread. It was...how do I put this....un-funny. Your pun was so bad it didn't even make me groan.

Well, if you can't see the correlation between the now 3 threads encompassing this issue, started with the single posting of an ad for Nitrox computer class, and the MOF/NMOF, that's ok... The truth is, everyone is posting the same things over and over... there will NEVER be a solution, and no one's mind will be changed. Sounds very much like MOF/NMOF

 

[MikeFerrara]

Let's see now ... 1. It wasn't set to the gas you were using. 2. You had cranked up the conservatism to some unknown level. Yep. An excellent example of how not to use computers.

It wasn't meant as an example of how to use a computer (other than as a bottom timmer) and it worked GREAT for that. Of course I let it know everything that it needed to know. LOL. It is an example of a computer computing a dive in a way that I don't understand and it looke to me like it might be an example of a computer doing what you said that they don't do...I say maybe because I really don't know.

Most dive computers crank in conservatism in essentially the same way that gradient factors do in deco planning programs -- by reducing the M-values. To a casual observer, it looks like it is a reduction in bottom times, but what really is being reduced is allowable compartment loading limits.


It may simply be that the allowable limits of the slower compartments had been reduced so drastically by you conservatism setting that you had exceeded the limits on the slower compartments. Reduce the M-values / gradient factor enough, and you will be increasing your deco obligation at 30'. I have a hard time figuring out how conservatism could be cranked up so far as to still be adding to deco time at 20'.

It had me baffled. I always meant dig into it and try to find out what it was doing but I never got around to it.

 

[The Kraken]

Personally, I dive with a computer AND analog depth and pressure gauges.

I plan the dive and use the computer to enhance the dive.

Should the computer become inoperative I fall back on the dive plan, if I haven't passed the NDL based upon the tables, and continue the dive.

So, I guess I carry the axe and chainsaw!

the K

 

[MikeFerrara]

While I agree (as my post in the other thread asserts), I must ask this in keeping with the thread topic.


If it is preferable to learn tables before learning computers because knowledge of tables enables one to make judgement calls in trusting computers, what should divers learn before the tables that will enable them to make judgement calls in trusting the tables?

In other words, where does this slippery slope end? Drawing a unit fluid cell and deriving a theory of gas decompression? If so, then diving is an activity for only the most brilliant mathematicians. If not, then at SOME point, one must trust something that someone else came up with, be it a computer or a deco table*. What, qualitatively, makes a table worthy of blind trust than a computer (again with the caveat that we aren't considering equipment failure)?

I think this is a great question and one that I've thought about a lot. All I can really say is that taking the time to compare different models and taking care in how I apply them in progressing to longer and deeper dives has seemed to work for me. I've never been in a chamber but there have been dives where I didn't feel so good after. I changed a few things, did the same dives again and felt fine. Certainly less than a controlled study but I do know divers who do dives with certain models and parameters that I won't do because, based on my own experience, I think there's a good chance that I'd get bent.

I know a few divers who have been bent diving a profile that their computers were happy with. In at least 2 cases I know for a fact that there were no obvious complicating factors. In both cases those dives were within the model being used but based on the way I set my software up I wouldn't do either of them.

In the end, it's just a model and there aren't any guarantees. Eventually you have to just try it and see if it works but I'd rather do it a little bit at a time and with some thought rather than just following lights.

I don't know that I see it as a table vs computer issue so much as a proactive vs reactive issue.

 

[kent_1848]

To get rid of all possibilities of equipment malfunction, I'm introducing a new system for all scuba divers. In your new kit, will be a 150' tape measure, and instructions on how many Mississippi's you can stay at any depth...1 Mississippi, 2 Mississippi, 3 Mississippi...

 

[The Chairman]

To get rid of all possibilities of equipment malfunction, I'm introducing a new system for all scuba divers. In your new kit, will be a 150' tape measure, and instructions on how many Mississippi's you can stay at any depth...1 Mississippi, 2 Mississippi, 3 Mississippi...

Bwahahahaha!

Unfortunately, you can't make the diver narcosis proof.