What computers are you using for tech dives?

[PfcAJ]

Unfortunately some divers just don't have the inclination or patience for this simple but rather time consuming approach.
I have been asked several times why I only had two BT and a slate and where was the computer?

Technical diving is a game of discipline and patience.

At least comments like that make it easy to spot the folks with a mindset I feel isn't adequate.

 

[TrimixToo]

To answer the OP's question, VR3 on left wrist, Petrel on right wrist. VR3 set to zero conservatism, Petrel set to 30/70 for deep cold water diving. I follow the Petrel unless things go pear-shaped. Eventually I will buy another Petrel (set much less conservatively) to supplant the VR3 but there's no big rush.

Used VR3s are a dime a dozen at $150 or so if you look around. Complex UI, no support, no spares (well, spare buttons can be had), but its more computer than you will need for a Long Time and a backup rec computer in gauge mode with tables will serve you well for quite a while. That said, the VR3 has a voracious appetite for batteries. SAFTs seem to last the longest.

But really, any Trimix computer will do to get you started if you plan going that route, and there are inexpensive things like Nitek HEs out there too. When (not if) things go wrong, something that knows what you are breathing when you go off plan (+ or -) is a huge plus. When the dive goes as planned, or approximately so, it's far less important.

 

[rongoodman]

I just unpacked my bags from the last time we went down that road. Do we have to do it again? So soon?

Serious question, not trying to pick a fight.

 

[runsongas]

petrel, although the ostc seems to be somewhat popular with europeans i have met and it seems to be a competent computer.

 

[DevonDiver]

I did an article and review/breakdown of the leading tech computers a while ago.

The Best Technical Diving Computers 2016

 

[KenGordon]

predictable mayhaps, but here's how I see your logic
Suunto Zoop-$215
Suunto Helo2-$524
CCR controller out of loop

Your total computer investment $739 for two computers
Perdix is $849. Is it worth $110 more than a Helo2+Zoop, every day of the week, it's not even a question. Is the Perdix worth $300 more than the Helo2? Considering it has an algorithm that isn't proprietary and currently goes against the state of the art in decompression research, has a screen that is infinitely better, and more functionality? I'd say so.
.

The OP already has a computer, as I already had a Zoop. His is more useful as it does multiple gases.

You cannot compare a Perdix to a Helo2 + Zoop as it is a single computer without a backup. Compare two Perdix and the difference is a lot of money.

The Helo2 and the Perdix both let you do deco dives. Yes the screen is nicer on the Perdix and that helps justify the price, but the key functionality is the same.

You claim to know that the Suunto algorithm is not supported by the current research but also that it is proprietary and nobody knows how it works. Can you not see those are contradictory statements?

And which of the settings on the Perdix are supported by science? 30/70GF? 45/95?

To get going the OP can spend £100 on a bottom timer, or £150 on a computer with gauge mode and go and do a bunch of dives with a twinset of 32% and see how it goes. He might find that he hates knowing he can't surface for 20 minutes and decides to stick with NDL diving.

 

[tbone1004]

@KenGordon the RGBM algorithm is what is not backed by current research. They have tweaked said algorithm but the basis of the algorithm is what is not currently kosher and we are unsure what was done.
You only quote the GF's in recreational mode, in tech mode you can do whatever you want so that isn't a valid argument.

note that I said to just use what he has for now, but I would 100% advocate against purchasing anything with Suunto's algorithm as being a complete waste of money if you plan to use it for technical diving

you say to get going he can purchase a bottom timer. You realize the Icon has gauge mode right?

 

[KenGordon]

@KenGordon the RGBM algorithm is what is not backed by current research. They have tweaked said algorithm but the basis of the algorithm is what is not currently kosher and we are unsure what was done.
You only quote the GF's in recreational mode, in tech mode you can do whatever you want so that isn't a valid argument.

note that I said to just use what he has for now, but I would 100% advocate against purchasing anything with Suunto's algorithm as being a complete waste of money if you plan to use it for technical diving

you say to get going he can purchase a bottom timer. You realize the Icon has gauge mode right?

Nor is GF backed by any research. it gives you the option to stay deep with the conceqences shown by the NEDU study.

He needs a back up. He ought to use the Icon as a primary compute and a bottom timer or cheap computer as a backup with a plan on a slate. That is the most straight forward thing to do.

I don't believe you can have done any 'technical' diving with a Suunto or similar, or in mixed teams of divers with those and Shearwater. If you had you would have found that your deco all comes out very similar in the end.

 

[Capt Jim Wyatt]

I have done a few 400fsw dives, a lot of 300fsw dives and a very large number of 150-300 ffw and fsw dives on my Shearwater computers and I am happy to report never being bent. Using 30/85 GF.

YMMV

 

[tbone1004]

@KenGordon I have, so let's play for sh!ts and giggles. I just downloaded Suunto's DM5 planner thing so let's run some easy profiles

160ft for 30 mins, on 21/35 using EAN50 as sole deoc gas on GF50/80-what I'd dive. Basically same total time as what Jim would have with 30/85 with a dive this short.
70-1
60-1
50-2
40-2
30-5
20-8
10-15
total-35

same dive, but using 30/70 since it came up
80-1
70-1
60-2
50-2
40-3
30-6
20-10
10-18
total deco-44

Suunto Tech as used on the Helo2 with P0 because I don't know what that actually means and it was default. Deep stops turned off
70-1
40-2
30-7
20-9
10-30
total-56mins

please explain how that is "very similar"? I can't actually force buhlmann to get that ascent profile with that long of a deco obligation. The closest I got was 80/60 *yes it was backwards*