Would you choose a "Technical." Dive Computer for "Recreational." Diving.

[boulderjohn]

Several years ago I was diving out of a resort in the Philippines. All of the dives were within recreational limits, with some being of a deeper nature off of boats and some being shore "muck" diving on the house reef. Of course I did not reconfigure my gear between dives, and that especially included the computers, since I needed to maintain accurate tissue loading.

On one of the dives on the house reefs, I realized I was a tad overdressed, especially carrying two Shearwater computers. I was in about 30 feet of water, with a planned dive time that could not possibly come close to using all my gas. It occurred to me that if that were the only kind of diving I were doing on that trip, I would not need much equipment at all. I would not need any computer, let alone a technical one. I would not need a depth gauge. I would not need a pressure gauge. I would not need a watch, unless I wanted to make sure I was out in time for lunch. Any of that equipment would simply be for added convenience, and the value of that added convenience would depend upon my personal feelings.

It all depends upon your dive needs. That basic diving I just described requires nearly nothing. Technical diving requires serious equipment. There is a wide range of needs in between. I certified a couple of friends a few years ago, and they have now logged well over 150 dives, all at the recreational level. We do a fair number of dives together each year, with me wearing Shearwaters and them using basic recreational computers that provide them with all the information they need.

 

[dmaziuk]

It occurred to me that if that were the only kind of diving I were doing on that trip, I would not need much equipment at all. I would not need any computer, let alone a technical one. I would not need a depth gauge. I would not need a pressure gauge. I would not need a watch, unless I wanted to make sure I was out in time for lunch. Any of that equipment would simply be for added convenience, and the value of that added convenience would depend upon my personal feelings.

On at least one muck dive here the briefing included "I recommend leaving your computer topside because the bottom here is above the no-limit depth, whereas the muck here may get in your sensor openings etc. and gunk up your expensive computer".

 

[stuartv]

I said this in the other thread and I'll say it again here. It is sad/funny how many people take the question of "what would YOU do" and twist that into a need to expound on what OTHER people SHOULD do.

Second, I reject the notion that there is such a thing as a "tech computer". Instead, I assert that there are only "tech-capable computers" (and recreational-only, or non-tech-capable computers). I think the distinction matters. Saying that there are tech computers and asking if you would use one for recreational diving implies that you are using something other than the right tool for the job. Technical diving IS recreational diving. Just a subset of it. As there is a subset of dive computers that are tech-capable. A tech-capable computer is still a recreational computer.

Asking if you would buy a tech computer for recreational diving is like asking, would you buy a 3/4 ton pickup if you were only hauling 1/2 ton-sized loads? Sure. Why not? It might be a little expensive - or it might not! But, there is no downside that is inherent to being tech-capable. The Shearwater OC Rec mode is proof of that. A tech-capable computer certainly CAN be hard to use, cryptic, and unfriendly to new divers. But, that is because of poor UI or whatever - not anything that is inherent to having tech capabilities.

if the recreational user isn't shielded from the technical features somehow, it will lead to errors in use and potentially the diver will get hurt. For beginner divers, it is VERY confusing and intimidating to say the least and I have seen and dealt with these beginner divers putting in the wrong configurations/settings in the computers where they almost got hurt.

Specific examples, please? Seriously. How did someone almost get hurt?

I note that the DSAT algorithm employed by MANY recreational divers' computers is approximately the equivalent of Buhlmann ZHL-16C with gradient factors of 95/95. MANY people have completed MANY dives with that algorithm, safely. So, I am inclined to reject any suggestion that somebody that was about to dive (just for example) a Shearwater set to GF99/99 as an example of someone who "almost got hurt".

I'm going to say that I have seen a lot more posts in the last 5 years of people who were confused and intimidated by a Geo or Atom than I've seen from people who were confused by a Perdix.



Finally, to answer the OP, yes. I do choose to dive a tech-capable computer, even on recreational dives. I do so because my computers also have the best screen and ease of use. And they allow me to view information about my tissue loading that, I THINK, allows me to complete my dives with more margin of safety against DCS, as compared to any of the recreational dive computers with which I am familiar. E.g. I can view my SurfGF and make my final ascent based on that. I still have my Oceanic Atom 3.0 and I could use it, so it's not simply a case of using what I have. I could choose either on every (open circuit) dive. I choose my tech-capable computers, even when I don't need the tech capabilities. Because the other parts are still better and the tech capabilities have no downside.

 

[boulderjohn]

Many people consider the critical factor in making a computer to be a tech computer to be its ability to plan dives using helium. Recent research indicating that there is no such thing as a helium penalty suggest there there may be no need to include helium in planning.

 

[Bob DBF]

I bought my first computer about ten years ago, after fortysomething years of diving. I picked up a rec computer because it was less expensive, and my tech type dives were much less frequent and I was not really interested in changeing my methods at this late date.

My feeling is, that for a rec diver, it the computer meets your needs and budget, it's your choice. A tech diver may need a tech computer or a rec computer in gauge mode may be good. It's all about wants, needs, and budget.

 

[stuartv]

Many people consider the critical factor in making a computer to be a tech computer to be its ability to plan dives using helium. Recent research indicating that there is no such thing as a helium penalty suggest there there may be no need to include helium in planning.

But, the determination of "no helium penalty" concluded that there is no helium penalty because dives without helium need to have the extra deco time that helium brings into the plan. So, using a computer that does not support helium to do the kind of dives that require helium would mean that the computer would prompt for less deco than it "should". I.e. less deco than it would if it knew about helium - which the recent research indicates you should do.

Unless there is some computer out there that has had its algorithm and parameters updated to actually reflect the recent research about the helium penalty, I think it would be a serious mistake to use any computer for trimix diving that does not have support for helium.

 

[ATJ]

Many people consider the critical factor in making a computer to be a tech computer to be its ability to plan dives using helium. Recent research indicating that there is no such thing as a helium penalty suggest there there may be no need to include helium in planning.

I've never done any training in trimix so perhaps I don't understand the use of helium... but...

Isn't the idea of helium is that it is an inert gas that can be used to decrease the amount of nitrogen (which does have a penalty) in the mix without increasing oxygen (which also has a penalty)? So, at the very least from a planning perspective you need to be able to say there is less nitrogen and/or oxygen in the mix.

 

[Diving Dubai]

Interesting reply? I suggest researching it, and coming to your own opinion, interpretation, and conclusion.
Cheers.

Perspective:

Uk system Deco is built into core training, Accelerated deco is just a bolt on course. So my delimitation is Technical = Trix mix or CCr

US system there is a huge "Song and dance" with Tec (or Technical being anything past 40m or any deco), with divers then making a huge issue that they're taking a AN/DP course which must elevate them in some way.

This translates almost into an equipment cult following "You (I) must have"

Whereas diver with sufficient experience have learnt what functions/attributes are a must have vs what's a nice to have

Manufacturers (not just of computers) reserve the best tech for their higher cost (tech) models. So lots of older divers get into top of the range computers for the screen readability (As well as those diving low vis)

Those of us with failing eyesight don't like to admit it - human nature avoiding reading glasses and prescription masks etc - we hate to admit we're getting old, so some of us will come ups with other "justifications"

I could quite happily make any of my dives - which are pretty agressive and by most are considered tech) on any computer that allows a gas switch

Whether I could read it or not underwater is a different thing altogether - and I'd rather keep my stress levels down by not shouting at a stupid ill thought out menu system.

I've dived Shearwater, OSTC and Eon (OSTC the least with only 100 ish dives) they're all much the same, behave the same way under water and the choice between them comes down to minor personal preferences (least annoyances)

The important think is to spend money wisely - No point having fancy gear if you can't afford to go diving - or can't because you've not invested in the right gear at the right time (Drysuit)

If someone comes into the shop for a new computer - I'll talk them through all the options, if their heart is still set on a Teric and they can afford it, I'll sell it to them and it's more profit for the shop - I tell them that too

Although in our area the D5 is the hot seller because of its colour screen and price difference

 

[The Chairman]

I am sure I am affected by narcosis even shallower!

Every atmosphere is like drinking a martini.

As an aside, Shearwater is making an announcement on Thursday that will impact this discussion. While they aren't the only PCD manufacturer, they seem to be the most trusted on SB and are my goto. Yes, I do know more, but I'm going to let them make their announcement first.

 

[hammet]

If I didnt already have a teric and if shearwater came out with a cheaper version of the teric that had just rec diving functionality with AI, I would definitely snap it up. I have no need for multiple gasses or mixes other than nitrox. I dont do deco. And I would be fine with just having 3 or so basic GF options (conservative, etc) rather than an infinite number of choices.