Shearwater Perdix AI

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You get what you deserve . . .As long as wireless AI works, is reliable & safe for you and you're having fun dives with it -->then that's all that really matters!
Again - saying "you get what you deserve" sounds like you are suggesting wireless AI is a bad thing which is just plain silly. I laid out what I see as the benefits for me and I still have my SPG if for some reason the AI fails, so how is this a negative? It's using technology to improve the overall experience, in my opinion - but I give up on this discussion...
 
You don't need wireless AI as an expensive training wheel. . .

In what way is a wireless AI computer a "training wheel" that a regular SPG is not? Aren't they both providing exactly the same information? While they may use very different technologies to determine pressure, the end result is identical: A pressure readout that the diver can see. They both deserve (or not) your derogatory characterization equally.
 
We've all been given the instruction and basic instrumentation to perform this fundamental and vital task in our beginning open water course.

Wrong. You're making a habit of that!

If you're so narced that you can't comprehend or account for what a simple SPG is telling you, then you should abort the dive. Purchasing a wireless AI isn't going to solve the root problem either.

Wrong again. If you are so narced that you can't do the arithmetic to combine a psi reading and a depth reading in feet to an amount of time, well you might not actually be narced at all, as the arithmetic for people using Imperial instruments actually isn't that easy. BUT, regardless, a computer that has any form of AI absolutely will solve the problem for you.
 
Wrong. You're making a habit of that!
Wireless AI/GTR is the illusion compensating for what you didn't retain or apply from your basic open water through your present intro tech/wreck courses. The cause of this is understandable when you read the following short and simple reply down below regarding US Imperial Units. . .
Wrong again. If you are so narced that you can't do the arithmetic to combine a psi reading and a depth reading in feet to an amount of time, well you might not actually be narced at all, as the arithmetic for people using Imperial instruments actually isn't that easy. BUT, regardless, a computer that has any form of AI absolutely will solve the problem for you.
Don't get CO2 narced by physical exertion: the solution for that is utilizing a less dense breathing gas along with a scooter/DPV as needed for mobility at deep depth --a wireless AI obviously won't do this for you.

As for arithmetic using harder more cumbersome US Imperial Units:

-->which is the quicker much easier subtraction arithmetic to see & figure:
3000 minus 1160 equals 1840 PSI?

Or: 200 minus 80 equals 120 BAR???

Do you have a clue now Stuart?
If not then you need to go buy a wireless AI. . .
 
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@Kevrumbo
I read your profile. I noticed you went thru GUE for your open water (OW). When I went thru OW with Padi, we used a wheel to plan dives. Many OW divers use computers when learning how to dive nowadays. I also noticed your profile does not list any instructor certifications. Which makes me believe that you are not really in touch with the deficiencies in the current prevailing OW curriculums. i would suggest you review the certification requirements of the certification agencies that issue the most certifications before assuming to know what is taught.
 
When I buy my new computer (it will be the Perdix AI) I am buying it for a few reasons:
1) Knowing pressures at a glance. Yes I have a fair idea of where it is going to be with a bit of experience.
2) Puts gas information in the same place as the rest of my information such as heading, depth.
3) AI allows me to look at my SAC in real time both while in the water and on the surface. I can see at a glance what a change in behaviour (kicking harder in an unexpected current, staying a few minutes longer at a depth) does to my dive time. That allows me to be better prepared the next time.
4) If I am diving an unfamiliar dive site, using new gear etc then my SAC might be way off what is "normal".
5) At this point in my diving I have only a general handle on what my SAC actually is as it covers a wide range due to the wide range of dive types that I have done to date. Which do I rely upon to work out the real SAC? The course dives (stressed due to it being a course), shore dive, the shore dive where the current changed halfway through, the shore dive where we had a lost buddy situation, the night dive on a reef, the night drift dive, the wreck dive, the wreck dive in surge, the night wreck dive. I don't have a bank of standard dives to work out what my SAC actually is because virtually all my dives were under different conditions and there is no "standard" set to work from.
6) The standard "take my gas at 5 mins and work out what I should have" works ok on square profile dives but on a typical shore dive here we might start at 6m, work out to 15-20 following the slope (which isn't necessarily at a fixed angle), travel at that depth for a while, then come back up along the slope and finish the dive with a shallow leg (which includes the "stop"). Not that easy to work out "on the fly" gas. I might have a general idea as to what I might use but accurate? No chance as there might be different currents on each leg.

@Kevrumbo - are you aware of anyone ever getting into trouble underwater from having more information such as that provided by AI?
 
- are you aware of anyone ever getting into trouble underwater from having more information such as that provided by AI?
No, but I'am also not aware of someone getting in trouble by not having this information through AI :wink: Let's face it, AI is a gimmick. A usefull gimmick, but not something you need or even something you should need. If AI solves a problem for you you better solve the problem first.
 
Doesn't how easy it is to monitor gas usage manually depend on the predictability of one's dives? Sure, if you dive a square-ish profile, it's easy to use your known SAC rate to estimate how much your SPG needle should drop in 5 minutes at your current depth. For cave and wreck diving, etc., it works fine. In that kind of diving, the diver also takes an abundant supply of gas, carefully planning the volume needed for the dive and leaving plenty of reserve for contingencies. If he brings enough gas and sticks to the plan, what his SPG reads should not affect whether he can get out safely. He just checks it now and then to confirm what he predicts it will read at any given point in time. Time, not gas, is likely to be the more significant parameter to monitor. He knows at about what time he will have to turn the dive.

In contrast, I can understand why AI is attractive to people whose typical dive plans involve meandering up and down over something like a reef, stretching their gas supply as far as they believe it can safely be stretched, leaving only a relatively small reserve--the proverbial "be back on the boat with 500 psi" kind of dive. AI's calculation of gas-time remaining helps this kind of diver maximize gas time the same way a computer's calculation of NDLs helps this kind of diver maximize bottom time. If I understood correctly, I believe Stuart pointed out the inconsistency in an argument that it's okay to rely on a computer's calculation of NDL but not okay to rely on a computer's calculation of GTR. I would think those who are okay with stretching no-deco time would be just as okay with stretching their gas supply. I still use an SPG because I enjoy the simplicity of it and was trained to do it that way. Also, I like to leave large safety buffers and am often back on the boat with a large amount of gas left, not to mention no-deco time left. However, if I were less risk-averse and willing to leave smaller safety buffers, I could envision how riding my computer's GTR display might allow me to extend my bottom time the same way riding my computer's NDL display might allow me to extend my bottom time.

I can't say I appreciate the advantage of being able to see my gas pressure on my wrist rather than a separate SPG, but others have said that it can be helpful in certain situations, such as when you're hanging on for dear life in a current. I don't foresee myself diving in conditions that are so difficult that I can't easily check my SPG.

As far as the data logging capability of AI, I guess some people find analyzing their data to be a fun exercise, but I sure don't. I calculate my SAC infrequently, and if I am planning something that I know is likely to stress me, I simply figure I'll need more gas than my SAC would indicate, maybe using a figure of 1 cfm if really stressed. I see no need for, and would derive no fun from, minute dissection of logged data. But some of you may. I think I referred to you (in good fun) as data nerds earlier in this thread or a similar one. If logging and analyzing dive data floats your boat, have at it. Some people just enjoy the idea of control panels with lots of data and measurements and that sort of thing. A surprising number of divers, especially tec divers, seem to be engineers and scientists. I'm a former engineer, and I don't enjoy numbers as much as I used to. I'm looking forward to the day when I can measure time in units of a season. Until then, I'll reluctantly deal with minutes and PSI to the minimum extent necessary to safely dive.

As others have repeatedly said, we're all different. For some kinds of diving, AI may provide benefits, and for other kinds it may just be an expensive toy. Again, whatever floats your boat.
 
AJ:
No, but I'am also not aware of someone getting in trouble by not having this information through AI :wink:Let's face it, AI is a gimmick. A usefull gimmick, but not something you need or even something you should need. If AI solves a problem for you you better solve the problem first.
By that logic, the SPG is a gimmick too... not all of us are claiming that AI solves a problem - however, it certainly provides a more convenient way to view tank pressure versus the SPG as well as additional and very useful automatic data logging (and GTR as well).

BTW - the Perdix AI manual is now up on the Shearwater Site!
 
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AJ:
No, but I'am also not aware of someone getting in trouble by not having this information through AI.

You've never heard of anyone running out of gas because they miscalculated (in their head) the amount of time their remaining gas supply would last? And we're to take your opinion on AI and other diver safety issues seriously?
 

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