New tech diver seeks computer advice

[TSandM]

TEarrington, I think what you are learning in this thread is that there is a wide range of approaches to technical diving, some of which is related to what KIND of technical diving you are doing (eg. square profiles on wrecks) and some of which is related to what kind of training you have taken and what you have been taught.

A lot of technical divers have planned their dives on laptops, using decompression software, and plotted contingency profiles, and transferred all of that to slates or wetnotes. Thus there was no need or desire for a computer to be doing an iterative calculation of decompression status during the dive. Some divers are using a curve-fitting process, which allows much of this to be done mentally. Again, no need for a computer as such.

Some divers plan their dives with software, but prefer to execute them with a computer that will take into account deviations from the original plan which might not be covered by contingency plans.

What kind of gauge you want depends on which of these strategies you end up using. Decompression computers that manage helium-containing gases are quite expensive, so buying one before you know where you are headed may not be the best use of funds, unless you can come up with another reason why you particularly want that gauge (as I did, with the X1, because I can read it).

Mentally tracking the dive, figuring the average depth, and monitoring your own decompression status is something most of us had to practice for a while before we were good at it. Letting the computer run as a computer during that period was a safety factor -- but I know of at least two of us who eventually forgot to reset the computer for Nitrox on a recreational dive, ignored the information the computer was giving us and bent it thoroughly. That usually results in the device going into gauge mode as soon as it stops sulking.

 

[DaleC]

IMO, the best way for you to accomplish this goal is to identify the classes that you think you want to take, research them, talk to others who took those classes and talk with instructors. Find out what equipment is required for the class and why and once you've completed the class you'll have your own foundation for determining what you need and more importantly why you need it.

I was thinking this from reading the OP. Not speaking for TEA (I don't know her intentions) but some thinking about the training path might help clarify which things to focus on and in which order.
Perhaps some who have taken multiple courses can comment on whether bouncing from say Adv Nx/Deco to Cavern to Tech to Cave is getting the best bang for limited bucks progression wise or whether one would be better off following a more linear path like Adv Nx/deco, Tech I, Tech II etc... depending on how much time one planned to spend on each given activity (recreational diving, shipwrecks, caves).

 

[TSandM]

I don't know . . . I've done a bunch of classes, and not in any particular order. I did decide several years ago that I wanted to cave dive, and did several classes with that end in mind, but not all of them had anything to do with caves. One was Fundamentals, which was simply to improve my overall diving skills. One was a wreck workshop that I did as a way to get overhead training in open water. Another was an introductory technical class that I did to get bottle-handling experience before going for my Cave 2 class, where stages and deco bottles would be used.

So I think you can sometimes use one type of class to fit yourself for another. I believe one of my Cave 1 buddies was using that class in part as a runup for his Tech 1.

 

[Colliam7]

Some divers plan their dives with software, but prefer to execute them with a computer that will take into account deviations from the original plan which might not be covered by contingency plans.

In training, we were religious about planning with laptop software, transferring the information to slates and back-ups, and following the plan, even if computers cleared much earlier than our pre-determined plan. Now, I am a little more flexible, and still plan the dive, transfer information to slates, follow the deco schedule on the ascent, and make the call at the 20ft stop about whether to follow the computer or stick to the plan. I dive with a X1, primarily for the reasons most people do - the phenomenal display AND the availability of time in seconds - as well as a more mature Nitek He. When both clear at my 20ft O2 stop, I usually surface, even if I have time left on my original schedule. If they haven't cleared by the time I reach the end of my planned deco stop, I stay until they do. It is a form of redundancy.

What kind of gauge you want depends on which of these strategies you end up using. Decompression computers that manage helium-containing gases are quite expensive, so buying one before you know where you are headed may not be the best use of funds, unless you can come up with another reason why you particularly want that gauge (as I did, with the X1, because I can read it).

Fully agree. Do some research now. If funding is not a critical issue, you may want to invest in a X1 - Liquivision has recently lowered the price again. But, based on your posted information you really don't require an expensive multigas computer right at the moment.

... but I know of at least two of us who eventually forgot to reset the computer for Nitrox on a recreational dive, ignored the information the computer was giving us and bent it thoroughly.

And, computers can be annoying, because they can't read your mind, generally don't monitor the gas you are breathing so that the user is relieved of responsibility for (re)setting them, and do have a tendency to want to sit out some dives when the user overlooks something, taking the attitude, 'OK, dumbass, when you figure out what you're doing, let me know, and I'll consider going diving with you again.'

 

[TEArrington]

Thanks again to all. TSandM, DaleC, and Colliam7's most recent posts definitely spoke to me. Two out of three of you are on the other coast from me -- too bad cause I'd love to dive with you.

For those curious, I'll offer some more clarifying information. I love learning, and hope I never stop. I have an amazing set of instructors at my LDS who give me great advice and guidance. The reason I posted the question here is exactly what some folks have pointed out -- everyone has at least one opinion on gear, and in asking someone what they like and why I usually learn something. I prefer not to hear just one person's opinion on gear, even someone I completely respect, without getting an alternate point of view before I decide what will work best for me. TSandM said it well "Some divers plan their dives with software, but prefer to execute them with a computer that will take into account deviations from the original plan which might not be covered by contingency plans." That is what I am looking to do. I get that a correctly functioning computer is still only as good as the information we put in and the response we have to it, but I prefer having one.

I have such a love for diving and learning, and have tried to develop my skills broadly (e.g., specialty classes and diving in a variety of locations & dive conditions) and deeply (focusing on a specific set of skills to really improve them with a purpose like my focus on wreck diving). Over this year I have taken/am taking several tech classes to learn the theory and practice on dives at planned trips. The cavern class came about when we planned to go cenote diving in Mexico. That turned into an interest in trying basic cave diving in the future, maybe next year in FL. My favorite thing to date has been wreck diving, and that's where the other tech classes have come in. I'm practicing locally at the quarry so I can do deep dives to some cool wrecks in Bonaire in June, St Lawrence in Sept, all getting ready for an amazing trip to Chuuk this November. I have no idea where my love of diving and learning may some day take me in terms of learning and improving skills, new dive conditions, and required equipment. Thanks to whoever it was that said equipment may only work for your style of diving for 2-3 years. I thought that was due to my improper planning, but maybe that's just the way it is.

I've taken some time to play with the Liquivision X1 and Shearwater Predator, and Suunto HelO2 was an option I noted but have not yet tried in a store. I'll keep researching and figure out what to do, but for now I am definitely making use of a BT, tables & software. I'd still like a computer as another point of data, but I will take my time picking it out.

 

[TSandM]

TEArrington, maybe we'll run into one another in a Mexican cave one of these days!

 

[Web Monkey]

I'm new to tech diving and am considering purchasing a new dive computer. I'd like advice (flame and rant free if possible) from some more experienced folks. I got some really nice advice from folks at my LDS, and I'd just like to see if a larger audience has anything else to say.

I like computers more than most people.

When I was younger, I'd build them, and for the last 30+ years, I've written all sorts of software including embedded systems (the type of thing that runs inside a dive computer).

And I won't trust a dive computer with my life.

Computers are great for no-deco dives where if it fails, you just surface with your buddy and say "Too bad. Dive's over." They're not great when you have some mystery deco obligation and have no clue where or how long it is, and your computer says something un-helpful like "E7".

My personal preference is vPlanner and a printed dive plan stuck on a wrist slate with clear plastic packing tape. That way I can read it and give it a sanity check before the dive, and no matter what happens, I know that my wrist slate will not suddenly decide to misbehave.

Terry

 

[texdiveguy]

Most quality dive computers have a 'gage mode'....great for deco dives along with your (pre-planned dive schedule, computer generated--many good software packages on the market), you just don't need to invest thousands of dollars on OC diving computers as a tech diver.