Shearwater for a newbie ?

[dmaziuk]

You're assuming the lock-outs programmed into recreational computers are due to them actually not being able to complete their calculations, as opposed to being there simply to shield the manufacturers from liability.

See Hanlon's Razor.

Edit: I don't think it matters, actually. A recreational computer's job is to get you out safely. If you bend it to the point where according to its calculations it cannot do so anymore, then what difference does it make. It needs a cold reset to get its numbers back on track and you need a ride in a chamber. If you were using it properly, that is. Otherwise there's a canonical tech. support joke about taking a computer back to the shop for refund on the grounds of being too stupid to own one.

 

[dmaziuk]

@dmaziuk the computers that lock out are capable of finishing the obligations because they will let you finish the first dive.

Show me the code and I will believe it. Otherwise: maybe they do, maybe they don't. From general principles, their subroutines are limited in what they can do, and once you hit the limits, you have to do something. That I know.

 

[tbone1004]

Show me the code and I will believe it. Otherwise: maybe they do, maybe they don't. From general principles, their subroutines are limited in what they can do, and once you hit the limits, you have to do something. That I know.

and the reason we can't see it is the whole reason this thread derailed, because the manufacturers won't open it up. That said, a lot of the computers that do, use the same hardware as their decompression enabled siblings *having seen different computers boards*, so if the hardware is the same, then they wrote it in as a safety precaution trying to "help" divers. That may have been a hardware issue in the 90's, but not anymore

 

[Centrals]

I am still using a nearly 20yrs old Uwatec Aladin Pro Nitrox dive computer. It is as safe as any latest model from any manufacturers. This computer can only set O2% in 2% increment and doesn't even has back-light!!!!! And definitely won't be compatible with any latest PC. But it does not matter a bit to me.

I will never understand why people would queue overnight or longer for the launch of any new gadget!!!

 

[admikar]

I disagree. Let's say you are diving 50/80. Your first stop is where you get to GF50. Now you skip the stop, ascending to e.g. GF 70. The computer SHOULD keep you there until you are below the initial calculated GF line and then resume the ascent.

If I understand GF correctly, GF value changes from low to hi, so if you skip your stop on GF50, initial calculated line at your current stop is no longer 50 but some higher value, therefore deco should be lower, disregarding the point that off gassing gradient will be higher, reducing your remaining deco even more. Whether skipping that stop is smart or safe is different mater altogether.
To return to OP, if YOU THINK YOU NEED Shearwater, go for it. Right now I'm just a few dives ahead and dive Mares Matrix. I don't have problems with its matrix dot screen, what I don't like is I have no idea what deco calculations it is performing and I am going into AN/DP so "tech" DC would be nice. My goal is Perdix (since Predator and Perdix are on par regarding the price, no point of going "lower" model), Mares will go as back up in gauge mode.

 

[enduser]

Sometimes scubaboard is so silly. What are you guys even talking about??

To answer the ops question. If you have the money. Yes a shearwater anything is amazing. If you don't. Any ole mother pucker comp will do.

Move along...

 

[Centrals]

Sometimes scubaboard is so silly. What are you guys even talking about??

To answer the ops question. If you have the money. Yes a shearwater anything is amazing. If you don't. Any ole mother pucker comp will do.

Move along...

The OP came in with a question and we all gave our opinions.
As far as I am concerned, money is NOT the only deciding factor on the topic! Why should I pay extra for some functions that I would never require?

 

[Neilwood]

Personally I have a bit of experience (about 50 dives) and I decided to go for a Perdix AI from a Cressi Giotto.

Reasons for me to move:
1) Screen readability - in all conditions the screen is far more readable than the Giotto. Larger text, colour coded, OLED screen compared with black on grey.
2) With the giotto I was having to use the light (which is a case of holding one of the buttons down for a few seconds). Not a huge thing but if you are otherwise task loaded (such as shooting a dsmb etc), it does make things more awkward.
3) All the information in one place - Prior to the perdix I had a console clipped to my waist Dring, DC on my wrist and compass on the same wrist (right arm so left was free to control buoyancy). Now I simply look at the Perdix for pressure, depth, NDL, compass heading etc.
4) Night diving - Rather than have to light my DC up with either the torch or button (as well as having to hold the torch over the SPG to get it to glow), it is simply there ready and readable at all times.
5) Compass integrated - no need to have a separate compass so cuts down on wrist space used. Also very easy to work out headings (set the direction and it will show the reciprocal or offset from your current heading making it very easy to work out an out/back heading, square, triangular etc)

Did I need it? No but I do think it has helped me be a safer diver - less time faffing about with torches and buttons on the computer/spg to me equals more time being aware of surroundings depth etc.

If you have the money spare, then I would definitely consider it for the reasons above.

 

[rpowton]

Here's another vote for the Shearwater - not only does it not lock you out when things don't go perfectly as the computer thinks they should but if you foul up for example and realize you have the wrong gas mix selected you can change to the correct one (or even add a mix) as soon as you realize.
In addition I find the menu/select operation to be as easy and simple as it can be compared to other computers that I have used - various Suunto & Dive Rites - so not only do I get a flexible, easy to read technical computer it is pretty simple for newbies to start using from day 1.

 

[beester]

To the OP: you don't need it yet... any cheap dive computer will do for now. However shearwater (also ostc but topic is about shearwater) computers are very very good. From readability, to user interface, to reliability, to the fact that they (other technical computers as well obviously) use an open non proprietary model. Very very good stuff.

One point of warning: keep it in rec mode if you do, don't mess with tech and changing GF (gradient factors) without knowing what you are doing and what the impact of such changes is... you can get hurt.

Then some funny anecdotes on diving with both the shearwater petrel and my old suunto vyper. I normally dive with both in gauge (vyper stowed away on a double ender in my pocket as backup). But since a year or so I have been starting to use the petrel as a sanity check on my dives.

- Doing a 80m, 30' dive and having the vyper (by accident) switch to air computer... I didn't notice (it's in my pocket) but taking the gear out after the dive I noticed it being in error. So I uploaded the dive to what is it... suunto dive manager, or dm5 or whatever and the TTS was going into 4 digits before crashing out.
- Doing a 65m dive, when I was first playing around with using the petrel as a backup computer and not gauge. Previous dive ended on O² obviously. So this dive had a bit of a busy descend, keeping the team together in current, scooters, things going on... At 6m I see the petrel flashing red (high ppo²), I'm busy so I just click confirm and keep descending... about 5 min on the bottom when I do a regular full check (me, gas, plan, equipment, team) I notice my petrel and I have no deco, but I do have a PPO² of 7.5 and a CNS% of 999... mmmm maybe I didn't switch to backgas on last dive Makes sense not having deco when you are breathing pure oxygen, talk about hyperbaric therapy.