dudley moray
sisternofuselessknowledge
anyone use cochrane dive computers
how do you like it is it worth the money
how is the ease of use at depth?
how do you like it is it worth the money
how is the ease of use at depth?
d/c's
- Thread starter dudley moray
- Start date
SeaJayInSC
New member
I have several dive computers. None of them a cochranes, but I know a good deal about them.
What sort of computer do you have now? Maybe I can draw a comparison for you...
What sort of computer do you have now? Maybe I can draw a comparison for you...
dudley moray
sisternofuselessknowledge
i don't have one yet but i know the us navy is using them so they must be ok i looking at a cochrane commander i have only used tables and an electronic dive planner so far
SeaJayInSC
New member
Well, sure, but the US Navy also has used Force Fins, Mares HUBs and 100% oxygen rebreathers...
Cochrane computers are typically used for mandatory staged decompression diving, and are well-known for their ability to switch multiple mixes, such as trimix, EAN50 and oxygen... All on the same dive.
The problem with that is that most people who are doing that type of diving typically don't use computers at all - in fact, they do exactly what you're doing now - plan the dive and dive the plan.
What is it that you're looking to accomplish with a dive computer, and what attracted you to a Cochrane?
dudley moray
sisternofuselessknowledge
well just looking for a good computer that can do air and nitrox and grow with me, i like the dir idea so i want to buy once and have it for a long time. also planning on a ccr ticket some day and i love the idea of caving so i guess i'm going the tec route so trimix and maybe heliox are in my future and having a computer that can do those things makes sense but ultimately i want a bottom timer that can handle these gasses and has a good well accepted deco algorithm the one i'm looking at isn't a navy unit and the price is right !
i'm glad you've responded to my post here seajay i've read alot of yours and really respect your opinions on diving and equipment so thank you for your input !
i'm glad you've responded to my post here seajay i've read alot of yours and really respect your opinions on diving and equipment so thank you for your input !
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SeaJayInSC
New member
Freeze right there.
Computers are not DIR. They will not be allowed in class.
Take the class first.
Yep, freeze again. CCRs are NOT DIR either. GUE allows SCRs in their upper-level classes, but not until waaaay later.
Freeze again.
Computers don't work with caving. If a computer tells you that you've got 8 minutes to your NDL, but you're 4,000 feet back into a cave, what are you going to do?Caves = computers are pointless. You must plan the dive, and dive the plan. Practice it now (and avoid a computer) and you'll be vastly better off than the guy that has learned to rely on his computer.
"Tech" is a term that's made-up by those who are not "tech." People who are really "tech" divers don't consider there to be a difference between "rec" and "tech" diving.
Drop the mindset before you get to class, and you'll be better off.
In your DIR classes, you'll learn about standardized gasses - none of which are heliox. Heliox is rather pointless over trimix (and much more expensive), which you will learn as you learn to mix.
A bottom timer handles just one thing - time.
In your DIR classes, you'll learn to understand and do your own decompression requirements "on the fly," no computer needed.You'll be able to choose any one you want - on the fly.
My bet is that you'll choose the same one that we have... Ratio Decompression. It was developed as a practical application of several different algorithms. Good stuff!Save your money and take a Fundies class. Call Doug at Extreme Exposure in High Springs, FL and book a trip... Spend less money, have a lot more fun, and learn why you didn't need a computer.
Thanks, man!
I hope I haven't sounded demeaning or patronizing here... My questions to you weren't setting you up - they were legitimate questions to see where you are now and where you are planning on going.
...And based on your answers, I've got an answer to your original question. You said, "Is it worth the money?"
The answer, for you, if you plan to cave and/or study DIR is a resounding no! Don't waste your money - you will not be able to use it in any of your classes... Nor will you want to, after you take your first couple of classes.
Save your money and go diving - you could spend like 1/3rd of the money, do a weekend of diving, and learn a ton through a Fundies course.
dudley moray
sisternofuselessknowledge
well that's kind of the answer i was looking for i have'nt seen a need for the over priced things it is all something you can do with a watch and some tables thank you
SeaJayInSC
New member
For what it's worth, I have a Suunto D6 strapped to my wrist all of the time... Topside or diving. Before the debut of the D6 (which is about the size of a large watch and made of stainless steel and glass), I wore the Suunto Stinger. A lot of us DIR types do/did.
My D6 is permenantly switched to "gauge mode." I find it to be a great timepiece, definitely telling of "diver," and it automatically switches from a watch to a gauge when it gets wet. It does a great job tracking depth and elapsed time and temperature, then shows a graph of the dive when the dive is done (matrix display) - a great tool for obtaining the "check mark" profile that makes for the best dive physiologically-speaking. Downloadable, too...
The D6 also has a very usable built-in digital compass (the best digital compass I've seen) that usually allows me to ditch the SK-7 that I still occassionally wear when navigation during the dive is the focus. (Bigger numbers on the SK-7.)
Thus, the D6 allows me to have all of my gauges - in a rugged, stylish package - all in one place. I wear it on my right wrist while diving (so that I can use it independently of my power inflator, dumps and lights - all controlled by my left hand) and on my left wrist when I'm not diving (so I can write easier - I'm right-handed).
Living with the D6 on a daily basis allows me to know the computer more intimately than I would otherwise, and thus not be "stumped" when I need to work it during a dive.
I'm sure that the D6 would also do very well as a dive computer - but it's just easier and better practice, IMHO, to always use procedural dive planning (and sticking to it during the dive) because it works for all diving and stays consistent for all diving. If I were to use the D6 for some diving and deco "on the fly" for other diving, I would be inconsistent and a "jack of all trades, master of none." Consistency is the pathway to perfection, I believe.
My first computer was a Suunto Vyper, worn on the right wrist, coupled with Suunto SK7 compass on my left. After my first DIR class (and about 100 dives on the Vyper in computer mode) it was really obvious to me that it would serve best if it was changed to "gauge mode" and left that way.
Over the years, I've also owned or dived Cochranes, Aerises, Dacors, Oceanics, and more... Some of which don't do "gauge mode," or I was too lazy to switch to "gauge mode." Some have aggressive algorithms, some are conservative, and some are aggressive in certain areas (like repetitive dives) and liberal in others (like bounce dives). The bottom line is - they all have their little nuances, and it's just as easy to learn ratio decompression (and therefore always know what's going on decompression-wise) than it is to learn the nuances and the software to operate the computer in the first place.
Here's an example:
Rule of 120:
Keep this in mind - when you go diving (first dive of the day), keep depth and time below 120. Diving to 20 feet? Max time should be no longer than 100 minutes. 60 feet? 60 minutes. 100 feet? 20 minutes.
For repetitive diving, be sure to spend a one-hour surface interval, then use the Rule of 110 - 20 feet? 90 minutes. 50 feet? 70 minutes. 90 feet? 20 minutes. Make sense?
This is an old US Navy addage, and a very simple method of approximating your "No decompression limits." Is it 100% accurate to the letter? No... It will likely be off by a couple of minutes one way or the other depending on the conservativism of the table that you compare it to... So remember, 60 feet for 60 minutes is your LIMIT. The further away you stay from that limit, the safer you are, so at 40 minutes, be thinking of making it back topside. Your body will thank you later.
An hour surface interval may sound like a very long time, but it's not - once you get topside, have a drink, change a tank, talk to your buddy about the dive and make a new dive plan, more than an hour has gone by anyway.
If you were to graph the Rule of 120 (depth = y axis and time = x axis) and compare it to the graph of say, a PADI dive table, you'd see that the PADI dive table is a lot more complex... And that it's a parabolic curve, rather than the Rule of 120's straight line. Thus, the Rule of 120 is actually quite conservative at the extremes (in 25 feet of water and in 110 feet of water) while being liberal by a few minutes in the middle (around 60 feet). With today's USN dive table, the Rule of 120 is actually pretty conservative all over, and if you're diving with EAN ("nitrox"), it's super-conservative. None of those specifics are really important, though... It's like asking someone what their alcohol tolerance is like. Is it important to know that you can consume 4.7 beers an hour before falling down? Is it important to point out that some people have better tolerance than others? Is it important to wear a super-pricey gauge that tells you where your BAC level is? Not really... Just know that at the party, one or two an hour is probably about as far as you want to go, 'cause everything just gets ugly after that.
The Rule of 120 is the same way... Think of it as a limit and stay away from it.
With that mindset, there's simply no reason that you should ever need a computer telling you that you have 6.7 minutes left. Your thought process shouldn't be, "Cool, I've got 6.7 minutes left..." It should be, "Hey, that's about as close to my limit as I want to get... Let's go get another tank and continue the dive..."
Does that make sense?
Hopefully, that'll make you wonder why you'd ever want to spend huge money on a Cochrane (or any other brand) of computer.
The Rule of 120, a great mindset, and a $20 G-shock watch from Wal-Mart coupled with a $20 depth gauge from Leisurepro will do you much better than any four-digit computer ever would.
...Now take the thousand dollars or so that you just saved and go do some diving - it'll give you a great excuse to practice the Rule of 120.
My D6 is permenantly switched to "gauge mode." I find it to be a great timepiece, definitely telling of "diver," and it automatically switches from a watch to a gauge when it gets wet. It does a great job tracking depth and elapsed time and temperature, then shows a graph of the dive when the dive is done (matrix display) - a great tool for obtaining the "check mark" profile that makes for the best dive physiologically-speaking. Downloadable, too...
The D6 also has a very usable built-in digital compass (the best digital compass I've seen) that usually allows me to ditch the SK-7 that I still occassionally wear when navigation during the dive is the focus. (Bigger numbers on the SK-7.)
Thus, the D6 allows me to have all of my gauges - in a rugged, stylish package - all in one place. I wear it on my right wrist while diving (so that I can use it independently of my power inflator, dumps and lights - all controlled by my left hand) and on my left wrist when I'm not diving (so I can write easier - I'm right-handed).
Living with the D6 on a daily basis allows me to know the computer more intimately than I would otherwise, and thus not be "stumped" when I need to work it during a dive.
I'm sure that the D6 would also do very well as a dive computer - but it's just easier and better practice, IMHO, to always use procedural dive planning (and sticking to it during the dive) because it works for all diving and stays consistent for all diving. If I were to use the D6 for some diving and deco "on the fly" for other diving, I would be inconsistent and a "jack of all trades, master of none." Consistency is the pathway to perfection, I believe.
My first computer was a Suunto Vyper, worn on the right wrist, coupled with Suunto SK7 compass on my left. After my first DIR class (and about 100 dives on the Vyper in computer mode) it was really obvious to me that it would serve best if it was changed to "gauge mode" and left that way.
Over the years, I've also owned or dived Cochranes, Aerises, Dacors, Oceanics, and more... Some of which don't do "gauge mode," or I was too lazy to switch to "gauge mode."
Some have aggressive algorithms, some are conservative, and some are aggressive in certain areas (like repetitive dives) and liberal in others (like bounce dives). The bottom line is - they all have their little nuances, and it's just as easy to learn ratio decompression (and therefore always know what's going on decompression-wise) than it is to learn the nuances and the software to operate the computer in the first place. Here's an example:
Rule of 120:
Keep this in mind - when you go diving (first dive of the day), keep depth and time below 120. Diving to 20 feet? Max time should be no longer than 100 minutes. 60 feet? 60 minutes. 100 feet? 20 minutes.
For repetitive diving, be sure to spend a one-hour surface interval, then use the Rule of 110 - 20 feet? 90 minutes. 50 feet? 70 minutes. 90 feet? 20 minutes. Make sense?
This is an old US Navy addage, and a very simple method of approximating your "No decompression limits." Is it 100% accurate to the letter? No... It will likely be off by a couple of minutes one way or the other depending on the conservativism of the table that you compare it to... So remember, 60 feet for 60 minutes is your LIMIT. The further away you stay from that limit, the safer you are, so at 40 minutes, be thinking of making it back topside. Your body will thank you later.
An hour surface interval may sound like a very long time, but it's not - once you get topside, have a drink, change a tank, talk to your buddy about the dive and make a new dive plan, more than an hour has gone by anyway.
If you were to graph the Rule of 120 (depth = y axis and time = x axis) and compare it to the graph of say, a PADI dive table, you'd see that the PADI dive table is a lot more complex... And that it's a parabolic curve, rather than the Rule of 120's straight line. Thus, the Rule of 120 is actually quite conservative at the extremes (in 25 feet of water and in 110 feet of water) while being liberal by a few minutes in the middle (around 60 feet). With today's USN dive table, the Rule of 120 is actually pretty conservative all over, and if you're diving with EAN ("nitrox"), it's super-conservative. None of those specifics are really important, though... It's like asking someone what their alcohol tolerance is like. Is it important to know that you can consume 4.7 beers an hour before falling down? Is it important to point out that some people have better tolerance than others? Is it important to wear a super-pricey gauge that tells you where your BAC level is? Not really... Just know that at the party, one or two an hour is probably about as far as you want to go, 'cause everything just gets ugly after that.
The Rule of 120 is the same way... Think of it as a limit and stay away from it.
With that mindset, there's simply no reason that you should ever need a computer telling you that you have 6.7 minutes left.
Your thought process shouldn't be, "Cool, I've got 6.7 minutes left..." It should be, "Hey, that's about as close to my limit as I want to get... Let's go get another tank and continue the dive..."Does that make sense?
Hopefully, that'll make you wonder why you'd ever want to spend huge money on a Cochrane (or any other brand) of computer.
The Rule of 120, a great mindset, and a $20 G-shock watch from Wal-Mart coupled with a $20 depth gauge from Leisurepro will do you much better than any four-digit computer ever would.
...Now take the thousand dollars or so that you just saved and go do some diving - it'll give you a great excuse to practice the Rule of 120.
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dudley moray
sisternofuselessknowledge
well like i said i got a citizen aqualand / watch and depth gauge, padi tables and that's all ive used so far and it works for me. i was looking at the computer cause the price was amazing 300$ that's less than i paid for my watch !
SeaJayInSC
New member
Yeah, my D6 was $600, and I got a smokin' deal on it... If memory serves, they retail for about $900.
Cochrans are known to be well into the quadruple digits.
In attempting to look for more information about this particular model, I Googled "Cochran Commander" and found that it's not a current model. There doesn't seem to be a whole lot of information on them.
A bottom timer and depth gauge never go out of style, and you never have to worry about software issues, firmware updates, or funky algorithms.
Cochrans are known to be well into the quadruple digits.
In attempting to look for more information about this particular model, I Googled "Cochran Commander" and found that it's not a current model. There doesn't seem to be a whole lot of information on them.
A bottom timer and depth gauge never go out of style, and you never have to worry about software issues, firmware updates, or funky algorithms.
dudley moray
sisternofuselessknowledge
any other suggestions on equipment ?
SeaJayInSC
New member
Nope. Take the money and go diving.
ARealmsLLC
New member
My dive watch/computer is the (shal we say old...as I have had it for years...but still works great!) Citizin Hyper Aqualand. I also use it as my daily watch as I love the size of it, plus...I have grown kind of fond of it. Worn through one wrist band already...right down to the kevlar or nylon weaving under the rubber. 
Seen here: http://www.skywatches.com.sg/citizenpromaster/digitaldepthmeter/MA9004.html
Like SeaJ stated....just get a good dive watch and everything else will come from your training as he stated.
Seen here: http://www.skywatches.com.sg/citizenpromaster/digitaldepthmeter/MA9004.html
Like SeaJ stated....just get a good dive watch and everything else will come from your training as he stated.
dudley moray
sisternofuselessknowledge
haha
haha
just reading over this old thread and it's amazing how green i was "heliox"
thanks again seajay your advise was priceless
haha
just reading over this old thread and it's amazing how green i was "heliox"
thanks again seajay your advise was priceless
SeaJayInSC
New member
Aw, don't feel so green... Heliox is a common gas used by many military operations. Most recreational divers don't use it because of the expense, and it's advantages over trimix is negligible. But the truth is, once you're mixing gasses, you can pretty much make anything you want - nitrox, trimix, rec triox, "heliotriox"... And yes, "heliox." The bottom line is that they all have their reasons for being.
dudley moray
sisternofuselessknowledge
i don't know if green is actually the term ... i know what i was thinking back then and the tec route was what i thought i wanted now after heeding your advise and diving 2-3 times a week this summer i decided i just want to be a good/better diver
SeaJayInSC
New member
Wow... Well, that's about as good a goal as any diver could possibly have. The longer, deeper, colder, and more boring dives will come later. :-D
...Just like the gear. The pricier, more complicated, less universal and less often used gear will come on its own. If you're anything like the rest of us, it'll end up breeding in your garage/shed at night, when you're not looking.
The best diver I know at 250 feet are the best divers I know at 20 feet. Congrats on getting some quality bottom time.
The longer, deeper, colder, and more boring dives will come later. :-D...Just like the gear. The pricier, more complicated, less universal and less often used gear will come on its own. If you're anything like the rest of us, it'll end up breeding in your garage/shed at night, when you're not looking.
The best diver I know at 250 feet are the best divers I know at 20 feet.
Congrats on getting some quality bottom time. 
