Hey everyone. I was at my LDS the other day and noticed a sign promoting their latest special which was a Nitrox Course through SDI. I have been thinking about getting Nitrox Certified so I thought this was a perfect opportunity.:D When I asked about the class I found out it was only taught using Dive Computers, no tables.:shocked2: Since I don't own a computer and won't own one for quite sometime I asked them if there was a provision for learning it with tables. They said no. Is this correct? If so why does SDI not want to teach tables? Seems to me they are limiting themselves in the market place.
maged_mmh
March 15th, 2009, 05:34 PM
why not go with another agency?
TC
March 15th, 2009, 05:37 PM
TDI offers a good nitrox course that includes tables.
:D
rongoodman
March 15th, 2009, 05:55 PM
Agree about TDI Nitrox. Our instructor added enough so that the TDI Advanced nitrox is mostly review. The Nitrox text is fairly new, published in 2006.
gotwake
March 15th, 2009, 06:12 PM
I agree with the other posters, TDI Nitrox class. I've just read the book and I'm taking the class at the end of the month. One of the LDS had the SDI computer class and one of the other shops offers the TDI Nitrox.
KJackson60
March 15th, 2009, 06:45 PM
why not go with another agency?
I was thinking about going with PADI but since this looked like a good deal I was willing to try them. As far as going with TDI I was under the impression (mistakenly apparently) that you needed to do the SDI course first.
I know that there are options to SDI. I was just wondering why they don't include tables with their courses. Thanks for the quick replies!:D
rongoodman
March 15th, 2009, 07:02 PM
I think SDI has just decided that computers have become so inexpensive and widely available that they make the most sense for recreational divers. I remember taking PADI AOW and being the only student in the class who really understood the tables when I walked in.
NudeDiver
March 15th, 2009, 07:23 PM
Could be the same reason why we don't learn logarithms using tables anymore either.
TC
March 15th, 2009, 07:58 PM
I was thinking about going with PADI but since this looked like a good deal I was willing to try them. As far as going with TDI I was under the impression (mistakenly apparently) that you needed to do the SDI course first.
I know that there are options to SDI. I was just wondering why they don't include tables with their courses. Thanks for the quick replies!:D
Some folks want to learn the tables and they make those courses available for them.
Some folks just want to use nitrox on their vacation and don't care about the math- For them you just teach them how to use and follow their computer properly.
Seems like a decent solution for everyone.
KJackson60
March 15th, 2009, 08:13 PM
I think SDI has just decided that computers have become so inexpensive and widely available that they make the most sense for recreational divers. I remember taking PADI AOW and being the only student in the class who really understood the tables when I walked in.
Well, I suppose that may be so. Except, I don't know anyone personally that is using a computer. And at $400.00 I don't consider that cheep, especially since I am just starting out and think an exposure suit, BCD, regs, etc have a higher priority than a computer. I also get what your saying about people REALLY understanding the tables. A stronger emphasize by the Certification Agencies would probably help there, but that is the subject for a different post!:rofl3:
Uhhhh.... Why don't they teach algorithms by table anymore?
maged_mmh
March 15th, 2009, 08:18 PM
Uhhhh.... Why don't they teach algorithms by table anymore?
coz along came vector analysis, calculus limits calculations, and wavelet transform :eyebrow:
KJackson60
March 15th, 2009, 09:18 PM
I think SDI has just decided that computers have become so inexpensive and widely available that they make the most sense for recreational divers. I remember taking PADI AOW and being the only student in the class who really understood the tables when I walked in.
Well, I suppose that may be so. Except, I don't know anyone personally that is using a computer. And at $400.00 I don't consider that cheep, especially since I am just starting out and think an exposure suit, BCD, regs, etc have a higher priority than a computer. I also get what your saying about people REALLY understanding the tables. A stronger emphasize by the Certification Agencies would probably help there, but that is the subject for a different post!:rofl3:
Uhhhh.... Why don't they teach algorithms by table anymore?
KJackson60
March 15th, 2009, 09:19 PM
Sorry about the double post!
KJackson60
March 15th, 2009, 09:28 PM
[QUOTE=TC;4282280]Some folks want to learn the tables and they make those courses available for them.
Some folks just want to use nitrox on their vacation and don't care about the math- For them you just teach them how to use and follow their computer properly.
Seems like a decent solution for everyone.[/QUOTE
Good point! Just wish my LDS was a little more accommodating to MY needs. At least on this point. Ah well, guess I'll do compressed air for awhile longer.
oly5050user
March 15th, 2009, 09:31 PM
Well, I suppose that may be so. Except, I don't know anyone personally that is using a computer. And at $400.00 I don't consider that cheep, especially since I am just starting out and think an exposure suit, BCD, regs, etc have a higher priority than a computer. I also get what your saying about people REALLY understanding the tables. A stronger emphasize by the Certification Agencies would probably help there, but that is the subject for a different post!:rofl3:
Uhhhh.... Why don't they teach algorithms by table anymore?
Welcome to world of diving..you should know how tables work so that you have an understanding what your computer is doing for you.
Here is a reason why computers can be considered "cheap"..
You need a watch to dive to keep track of bottom time-surface interval time-and to navigate with..cost of a halfway decent watch (SEIKO as an example) $200.Can it be done for less?Sure but how long will it last?
You need a way to keep track of depth-depth gauge alone $100.-spg depth combo $190...
A computer can pay for itself in additional time it gives you on a dive(multi-level capability) that pays for itself the first week you own it on a dive vacation doing 3-4-5 dive a day.We have a special with Scubapro running right now-buy a galileo computer-yeah I know ,its the most expensive they have,and a bcd with an air 2 on it and you get a FREE top of the line regulator(value of $689.)Look for deals on other vendors also.Computer does not have to cost $400--could be $50.-$100.-$150. less than that if you deal with the lds on a package deal.
udtfire
March 15th, 2009, 09:42 PM
as an SDI IT let me clear up some common misconception we require a comp for basic class because most divers use a computer and we use them to teach understanding of dive physics just as we use the tables for the same reason. the instructor has the option to teach tables if they or you wish. but at the basic openwater level you must use a computer in class. the instructors I know provide comp for the basic class. if you are diving euough to take a nitrox class the investment in that class would be wasted without a computer a computer pays for itself in bottom time. basic comp start at around 200 and your enjoyment and safety is worth that . stay safe and hope to see you in the water.
Dive Junky
March 15th, 2009, 09:57 PM
Hey everyone. I was at my LDS the other day and noticed a sign promoting their latest special which was a Nitrox Course through SDI. I have been thinking about getting Nitrox Certified so I thought this was a perfect opportunity.:D When I asked about the class I found out it was only taught using Dive Computers, no tables.:shocked2: Since I don't own a computer and won't own one for quite sometime I asked them if there was a provision for learning it with tables. They said no. Is this correct? If so why does SDI not want to teach tables? Seems to me they are limiting themselves in the market place.
SDI has developed a simple, yet safe and educational system for all of their classes. It took a little getting used to for me since I began as a NAUI instructor. I teach now for NAUI, SDI, and TDI. The one thing that drew you to the original SDI nitrox class was the cost. The class of course is not nearly as indepth as TDI or NAUI nitrox classes. Quite simply, 'You get what you pay for'.
texdiveguy
March 15th, 2009, 10:05 PM
Standard everyday recreational diving is so much more enhanced with the use of a quality dive computer now days. It is important I believe also to have a solid understanding behind the use of dive tables, but lets face it most recreational divers are using some form of computer in their diving.
KJackson60
March 15th, 2009, 10:09 PM
Welcome to world of diving..you should know how tables work so that you have an understanding what your computer is doing for you.
Here is a reason why computers can be considered "cheap"..
You need a watch to dive to keep track of bottom time-surface interval time-and to navigate with..cost of a halfway decent watch (SEIKO as an example) $200.Can it be done for less?Sure but how long will it last?
You need a way to keep track of depth-depth gauge alone $100.-spg depth combo $190...
A computer can pay for itself in additional time it gives you on a dive(multi-level capability) that pays for itself the first week you own it on a dive vacation doing 3-4-5 dive a day.We have a special with Scubapro running right now-buy a galileo computer-yeah I know ,its the most expensive they have,and a bcd with an air 2 on it and you get a FREE top of the line regulator(value of $689.)Look for deals on other vendors also.Computer does not have to cost $400--could be $50.-$100.-$150. less than that if you deal with the lds on a package deal.
I absolutly agree with your first statement about understanding how tables work so you know what the computer is doing. I also understand your point about buying equipment in packages to get a better deal. I will definitely be doing that when I am in a financial position to do so. Right now though I am just wanting to get more experience and further my knowledge base by diving and picking up training as it is available and I can afford it. So at this point in my dive life if I have $2-300.00 I am using it for diving (with rental equipment and the gear I own) and a class or two, funds permitting.
I have received some really great replies to this question. I would like to thank all of you for your interest.
ppo2_diver
March 15th, 2009, 11:03 PM
Hey everyone. I was at my LDS the other day and noticed a sign promoting their latest special which was a Nitrox Course through SDI. I have been thinking about getting Nitrox Certified so I thought this was a perfect opportunity.:D When I asked about the class I found out it was only taught using Dive Computers, no tables.:shocked2: Since I don't own a computer and won't own one for quite sometime I asked them if there was a provision for learning it with tables. They said no. Is this correct? If so why does SDI not want to teach tables? Seems to me they are limiting themselves in the market place.
It probably is the Computer Nitrox course that is offered by SDI. TDI's Nitrox course is taught with tables. SDI does allow instructors to include tables with their classes, so it is up to the instructor if he/she wants to add them or not.
I'm surprised that they wouldn't be flexible enough to teach you tables and rent you a computer for the class. If tables is something you want to learn, then look around for another shop/instructor.
Dive Junky
March 15th, 2009, 11:13 PM
It probably is the Computer Nitrox course that is offered by SDI. TDI's Nitrox course is taught with tables. SDI does allow instructors to include tables with their classes, so it is up to the instructor if he/she wants to add them or not.
I'm surprised that they wouldn't be flexible enough to teach you tables and rent you a computer for the class. If tables is something you want to learn, then look around for another shop/instructor.
He said they were promoting their latest special. I am sure they wouldn't be able to make a special provision for one student. I am sure if he offered to pay additional they would be happy to accomodate him.
NudeDiver
March 16th, 2009, 03:20 AM
Uhhhh.... Why don't they teach algorithms by table anymore?Umm...because "teaching algorithms by table" makes no sense whatsoever?? Which algorithms? Did you have any particular ones in mind?
Steve, SDI/TDI HQ
March 16th, 2009, 10:21 AM
I was thinking about going with PADI but since this looked like a good deal I was willing to try them. As far as going with TDI I was under the impression (mistakenly apparently) that you needed to do the SDI course first.
I know that there are options to SDI. I was just wondering why they don't include tables with their courses. Thanks for the quick replies!:D
I think the OP's original questions have been adequately answered and thanks to all of our members who contributed.
I would like to add a couple of small clarifications.
All SDI divers are expected to dive with a personal dive computer... NO EXCEPTIONS. the reasons for encouraging sport divers to use 21st century technology to help manage their inert gas loading should be self-evident.
But just in case: one could make a strong argument for the skills developed when using a good sextant, a chronometer and declination tables to fix a boat's position, but a GPS is more likely to give accurate information about location... and for the weekend navigator therefore, a GPS is a far better option.
We feel the same can be said for personal dive computers vs dive tables, EAN tables and manual calculations. PDCs simply represent the best possible practice for the sport diving community at large.
But there are divers who want more knowledge. For them, we offer Technical Diving International's Nitrox Course. It's all about tables, and working out nitrogen loading, MODs et al manually.
SDI nitrox is NOT a required prerequisite for taking a TDI basic nitrox course. It's the diver's choice and why we continue to offer both.
The SDI Nitrox course is available online and has been popular in that format for a couple of years.
Hope this sorts things out.
MikeSK
March 16th, 2009, 12:35 PM
FWIW..i totally agree about PDCs. They are far more accurate than tables, allow for more flexibilty, and of course...TONS easier to use.
Math of any sort except the basics is like greek to me :)
PDCs are coming down quite a bit and adequate ones can be had from $300 on up. Ones that can do air and nitrox are going to be more expensive.
KJackson60
March 16th, 2009, 11:07 PM
Thanks for the information. I will definitely look at TDIs course.
fletcherbg
March 17th, 2009, 11:47 PM
I agree. Pdc's are a much safer way to dive. For they are just so much more accurate about your loads. The industry should lean towards pdc's all the way around. For tables are just a little out of date to me.
ppo2_diver
March 18th, 2009, 12:49 AM
Not to hijack the thread, but what about the recalls that have been done on dive computers? PDCs should be taught because that is what many people will rent. However, divers need to know what happens when that computer fails and the theory of what is going on in their body. Basically, not to just blindly follow a computer.
ditch-diver
March 18th, 2009, 02:24 AM
... which is precisely why computer failure situations are presented to the class and how to deal with them. As far as 'what is going on in their body...' that is covered in the Physics and Physiology lectures..., along with being covered in the Section of the course that deals with the history of the dive tables, what they represented and how the computer evolved to do the job of the tables.
They are no more blindly following their computer than any OW diver is blindly following their tables...
Rick Inman
March 18th, 2009, 02:54 AM
...so it should be like a ten minute class, where you show the student how to program 32% into their computer, then it's dive as normal...keep your computer out of the red and that's it. No reason to talk about doing the funky chicken when you just follow the computer - all those old fashioned max exposure times and useless stuff.
The class must cost about $2.00. Oh wait. All that, "The history of," stuff.
... a computer pays for itself in bottom time.
And can someone do the math for me on how the bottom time pays for itself?
Wait. Sorry about asking for the math. Never mind.
FritzCat66
March 18th, 2009, 12:10 PM
While we're on the subject, isn't it just sad that nobody trains drivers on using a sextant anymore? Everybody's gone GPS nowadays. Man, are they going to be sorry when that computer fails! Nobody even knows how to calculate relative azimuth. Sad.
And what's with all these digital calculators? Don't even get me started on the superiority of slide rules!
I learned my tables because I had to for PADI classes, then promptly threw them away, got a great computer, and never looked back. Completely useless knowledge. I have no idea why they still teach those archaic things, I guess to justify their expenditure in developing them. So now it's just a hoop to jump through for your cert. I wish they taught around computers. Kudos to SDI for moving forward.
If the computer fails while diving, it's just like any other critical piece of gear that fails: you end the dive, and unless you can field-repair it, or brought some redundancy, or can borrow something else, that's it for diving until things are fixed.
Oh, and I don't know how to use a sextant, and nowadays I depend on the calculator program on my smartphone too, which doubles as a GPS with a Bluetooth receiver.
And my career is in digital medical imaging, replacing nasty, archaic, analog, chemical-soup film systems and installing among other things computer-aided diagnosing systems that pre-scan MRI and digital mammo images for problem areas - helping the reading physicians see things early on that they might never have noticed before.
Technological progress is great.
..unless you're Amish.
>*< Fritz
Steve02
March 18th, 2009, 12:16 PM
And my career is in digital medical imaging, replacing nasty, archaic, analog, chemical-soup film systems and installing among other things computer-aided diagnosing systems that pre-scan MRI and digital mammo images for problem areas - helping the reading physicians see things early on that they might never have noticed before.
Technological progress is great.
Well, I wonder why they even train physicians to read those scans then anyway - If a computer software program will do it.
I agree that computers are nice, and a lot of people really rely on them. However, I do feel a lot more comfortable just being able to plan out my dives ahead of time, even if I might not stick exactly to my plan.
I am engineer, so yes I do understand the value that computers add to our everyday lives. But I also understand the need to know how and why the computer is giving me the results that it is.
My $0.02.
Steve
FritzCat66
March 18th, 2009, 01:26 PM
Well, I wonder why they even train physicians to read those scans then anyway - If a computer software program will do it.
Things are moving that direction faster than most people realize. In large part because the systems learn from the human physicians - every diagnosis the system missed, every false positive, becomes fodder for the database, a tweak to the AI.
The first gaming computers lost to chess grandmasters, and it took a long time and many evolutions, but then eventually the AI bested the humans. The same will happen with computer-interpreted diagnoses. I've already seen huge leaps in progress in my field since I was installing the first generation in the 90's.
This is a good thing, a wonderful thing.
And already a large percentage of the interpretations made by the human physicians are no longer being transcribed, but rather fed through a voice-recognition engine - which again took a while to evolve (believe me, I've had to uninstall a few), but are now more accepted than not.
However, I do feel a lot more comfortable just being able to plan out my dives ahead of time, even if I might not stick exactly to my plan.
My computer already allows me to plan a dive, and "walk" through it. But I'll concede that function just isn't quite "there" yet. I think features like this will evolve to be even more flexible, useful, and powerful.
I am engineer, so yes I do understand the value that computers add to our everyday lives. But I also understand the need to know how and why the computer is giving me the results that it is.
Agreed, one should understand the limits of whatever technology one is using, whether it's a computer or a sextant. Or even a simple compass, a lesson I learned when failing my navigation checkout dives due to being too close to an old wreck that was skewing my readings.
Also agreed that someone must understand how and why the digital system functions - but that throws the technological knowledge required back to the physical and physiological theories behind the tables, not the tables themselves, which are already just a crude compromise.
The hardware and software engineers always have to know the science and technology - and I've worked side-by-side with engineers my entire career and have great respect for them.
A GPS has to calculate position based on minute timing and phase differentials between satellite signals, for example. But I don't want to do those calculations myself, I'll leave it to them - let them do what they're trained to do, and trust the device, also knowing its limitations. Likewise, I don't have to know how to calculate safe times using the modified Haldanean algorithms in my PDC, but I trust the technology and the engineers, and am also aware of the computer's limitations, what it can and can't do (like predict my future changes in depth).
But when it comes to performance in the field, I know my personal wetware CPU is affected by narcosis - even before I am aware of the effects. But the silicon CPU in my computer is not. So I also know which one I tend to trust more at depth.
>*< Fritz
DiveNav
March 18th, 2009, 01:42 PM
Hi KJackson60,
next week we are releasing a new version of our dive simulator (http://www.ediving.us/userHome.php) that includes an advanced Dive Computer - Nitrox capable.
Whit this new version You will also be able to plan one or more Nitrox virtual dives and see in 3D -while you dive - how the various combination of gas mixes / dive times / dive depths / surface intervals will affect your Nitrogen and O2 loadings.
We call this: "Learning while Playing" ;)
Enjoy it.
Steve02
March 18th, 2009, 03:58 PM
A GPS has to calculate position based on minute timing and phase differentials between satellite signals, for example. But I don't want to do those calculations myself, I'll leave it to them - let them do what they're trained to do, and trust the device, also knowing its limitations.
I think we may be saying the exact same thing. I have a GPS too, and the limit of my knowledge of their operation is about what you described above. However, I don't care how they work either becuase if it does crap out then I know how to read a map.
I guess my point is, while computers are great, great tools I don't want to have to rely on them soley.
And I agree, at a deep depth, where narcosis could effect judgement then I too would whole heartedly want to trust the computer moreso than myself.
CompuDude
March 18th, 2009, 08:17 PM
Apparently SDI believes divers should never have to actually think about diving.
The horror.
I agree that the GPS analogy is excellent... just not in the way FritzCat intended. It's one thing to teach divers to use a GPS, it's another thing to teach them that a GPS is the only solution, and that if it dies, you're screwed... rather than teaching them how to read a map as a backup. Same with tables. Computers are great, but if I'm on a trip to dive, as long as I have a depth gauge and a watch, I can dive tables if I don't have access to a computer (loss, damage, whatever).
uncleavi
March 18th, 2009, 09:13 PM
If you don't want to learn to dive with a computer, your best bet is to go to Lancaster PA and learn to dive with the Plain folk and stay away from the wicked ways of the English.
uncleavi
March 18th, 2009, 09:15 PM
I changed my mind, if you don't want to learn with a Computer, pick another agency.
ZKY
March 18th, 2009, 09:59 PM
Why is it that when I did TDI advance nitrox and deco proceedures we did tables and now with regular ndl recreational stuff they have to use a computer. Shouldn't it be the other way around being that the tech stuff is more critical?
When I took PADI nitrox they gave us a 32% table, a 36% table, and an equivilent air depth table that you could calculate any nitrox mixture up to 40% in combo with an air table. On the EAD table they also had an PPO2 saturation table on the back.
How do you program a typical computer to allow for deep stops without penalizing you thinking you're taking on more gas when in fact according to DAN's study, offgassing begins with deep stops and is much more effective than just going straight up to 15 feet like the computer tells you to do to avoid being locked out.
So does this mean that this computer idea is going to spread and they're going to have school children just use a calculator from the get go and they see no need to teach them basic arithmatic anymore? I guess they figure using your brain is archaic. Or is it that tables and theory take to much time and their profit margin goes down.
Rick Inman
March 18th, 2009, 10:11 PM
...next week we are releasing a new version of our dive simulator (http://www.ediving.us/userHome.php) ...
We call this: "Learning while Playing" ;)
No, we call this, "Spam". ;)
FritzCat66
March 18th, 2009, 10:46 PM
... It's one thing to teach drivers to use a GPS, it's another thing to teach them that a GPS is the only solution, and that if it dies, you're screwed... rather than teaching them how to read a map as a backup. Same with tables. Computers are great, but if I'm on a trip to dive, as long as I have a depth gauge and a watch, I can dive tables if I don't have access to a computer (loss, damage, whatever).
Doesn't fly: The problem with that analogy is the gear required even to use the tables. Unlike with the map, which requires no other gear to use, to use tables you've got other pieces of equipment that can break. In other words, to truly fit the GPS-to-map analogy, you would need to be able to go from computer-to-tables without any other equipment, but that's not the case: tables are useless without TWO other pieces of equipment: a depth gauge and a timer (plus the tables themselves makes three: they can't really break but can certainly be lost).
Since that's the case, with tables you're just pushing around which piece of equipment you're dependent upon, and that leads to the whole redundancy argument. If that's the case, I think the KISS principle applies, and one should just wear a second, backup computer rather than switching between two completely different methods (computer vs. tables).
Also, if on a trip diving with a computer and that fails, switching to tables without knowing what your N2 and O2 saturation levels are would be difficult. I guess a 24-hour rest, but even that doesn't guarantee pulmonary O2 levels are reset. Again with KISS: get one good computer and dive it. If you really want redundancy, get a backup computer and wear it all the time.
Either way, toss the tables or put them in a museum with the sextant - good call, SDI.
>*< Fritz
DiveNav
March 19th, 2009, 12:52 PM
No, we call this, "Spam". ;)
Why is that?
I believe the post was useful to the OP; he wants to learn more about nitrox and dive computers and our simulator can certainly help him with that
Give me a call if you want to discuss this further.
