My dive computer is too conservative, what can I do ?

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

Using a higher O2 (Lower N2) setting on your computer will give you longer bottom times than air settings. I do that all the time. I almost never set my dive computers to air. That’s because I almost never dive with Air. Some sort of enriched mix is in all my tanks at the moment.

If you want longer bottom times, dive the mix that will allow that. If you don’t already have a Nitrox cert, look into it. It’s really worth it. Don’t lie to your computer.

If you already have your Suunto set on the least conservative setting, then there isn’t really much you can do with that computer. You can probably get by by staying within the limits that Suunto deems necessary. A few were mentioned earlier (no short SIs, no sawtooth, etc). If that’s still not getting you where you want to be, then another algorithm is probably your only option.
 
How does the D4 help in your dive bag? Shouldn’t it be on your wrist or in a pocket?

I monitor my residual nitrogen. If I break the Teric in the morning, I may skip the rest of the dive on that day and start my next day dive with my Suunto D4. Based on the previous nitrogen residual record after 12-18 hours of surface interval, my residual nitrogen almost down to zero, like starting up a new dive with a new dive computer.
 
Hello hello,

Here's my problem. I've just bought a Suunto Zoop Novo, but I realise that the algorithm used is on average significantly more conservative than that of the dive computers of the people I dive with (for example Aqualung). I'm not at all in favour of excessive risk-taking, but I'm thinking more and more that Suunto's conservatism isn't really justified, since other computers allow longer NDLs at the same depth (again, I'm thinking in particular of Aqualung), and yet they're widely used by dive clubs all over the world, without causing a significantly higher number of accidents (tell me if I'm wrong on this point). I realise the same thing when I compare the NDL given by my Suunto with the PADI dive tables, which are also more liberal.

I'd also like to stick with my dive computer as I like everything else so much.

I was thinking of a solution that would allow me to slightly reduce the conservatism of my computer: set it to an O2 level slightly higher than the one I actually use (Nitrox 25% if I dive with air, for example), so as to obtain results close to the PADI dive table when I plan my dives with the computer.

Is this taking a risk? What could be dangerous?

Thx a lot for your responses !
i have the zoop also, change the personal settings to P3. i dove all summer long with a DM having a peregrine never had a problem.

The zoop is a entry level computer, basic but ok.

be safe
 
Strange you have too much conservatism with the Novo. The old zoops got deco under the shower.
I own a D5 from Suunto, a great price I won. But the first stopped working during a dive and showed under water: fatal system error, contact your suunto dealer.
It had warranty, so I did. I got a new one, BUT, and that is what I really don't like from Suunto: they did not give me a new screenprotect which was sticked on the broken one. And they also give me only a new computer with the used wristband. The band ok, but no screenprotector is what I really don't call any good customer service.

But ok, my second D5 is running. I have taken it together with my Shearwater to several dives. The shearwater is dived in 40/75. The suunto I did not adjust, so it will be the '0'. On most single dives, the Suunto shows more NDL than the Shearwater.
But if you get into deco with the Suunto, it is running up faster than with the shearwater.
Sometimes, you see some strange things when you are doing cavedives for example.
If you stay a long time around 12m, the Shearwater counts deco back. The suunto count deco up, so you get more deco. After a long dive with only ean32 as gas, and a max depth of 26m, both had the same deco, but this was due to the long time at 12 Suunto did not like.

But if you do just single tank dives and most are within NDL, the Suunto D5 is not reacting too conservative. I have tested this also on air dives, 4 per day in Bali, together with the Shearwater on air, 40/75, BO modus (I am too lazy to set it back to OC tec, I never found differences, even the manual states this is not the right way).

I have had students with the old Vipers and the Novo. The older ones got the '505' during dives, the newer ones not. The older ones really got deco under the shower as we call it.
The newer ones seems like to follow a 80 or so as GF-high if you use a Buhlmann as second computer. Suunto uses 'fused RGBM', but they tweaked it for sure in the Novo computers. And it looks like more a gf-high80 profile in shallows.
On dives up to 65m ( I haven't been deeper with my D5), I have not seen too long decos with the D5. But sometimes a deeper first stop than Shearwater gives. The only thing is, don't ignore it with Suunto, you will get the '505', instead of a recalculation which Shearwater does.

I have other requirements for computers than most recreational divers have, so most times the Novos are ok to use, together with the Pucks and such stuff. Recreational divers normally don't need recalculations for missed stops. But this is a big miss in my eyes in the D5, which is a semi technical computer (only does nitrox, but you can use a decogas, but sadly not change under water if you forgot a gas to put in).

So if your Novo is reacting strange, I would advice to borrow a second Novo from a divecenter or a buddy and see if same happens.
Are you diving strange dive profiles? Then a Suunto can react strange. Are you bouncing a lot? Look also at this. I have seen that Suunto can react different than Shearwater on such dives.

And if you still have a too conservative computer, buy another one. The mares Puck Pro is a good cheap one for recreational divers. The Shearwater Petrel or Perdix is of course top of the notch. But normally the Novo is not bad or too conservative.
...got deco under the shower... that s a good one 😂
 
I monitor my residual nitrogen. If I break the Teric in the morning, I may skip the rest of the dive on that day and start my next day dive with my Suunto D4. Based on the previous nitrogen residual record after 12-18 hours of surface interval, my residual nitrogen almost down to zero, like starting up a new dive with a new dive computer.

Keep it with you and you won’t miss any dives?
 
Keep it with you and you won’t miss any dives?

Missing a dive or two out of 25-35 dives in a trip is no big loss for me. Locking out my super conservative Suunto D4 while diving with my Teric is more of my concern.

If I take my D4 with me, I end up using D4 dive profile, staying shallow to keep it from locking out, while my dive buddies having a field day down there taking cool pictures of critters and treating my expensive Teric as a fancy bracelet.
 
But if you do just single tank dives and most are within NDL, the Suunto D5 is not reacting too conservative. I have tested this also on air dives, 4 per day in Bali, together with the Shearwater on air, 40/75, BO modus (I am too lazy to set it back to OC tec, I never found differences, even the manual states this is not the right way).

Try this:
1. Take both your D5 & Shearwater (at the same conservatism setting you had before) to a light DECO dive # 1 (light DECO means you pass 1 or 2 minutes of DECO and that DECO disappears as you ascend slowly to the shallow),
2 Do a short surface interval, say for 45 minutes.
3. Go another light DECO dive #2 and now see how much penalty you incur on your D5 relative to your Shearwater.
 
Missing a dive or two out of 25-35 dives in a trip is no big loss for me. Locking out my super conservative Suunto D4 while diving with my Teric is more of my concern.

If I take my D4 with me, I end up using D4 dive profile, staying shallow to keep it from locking out, while my dive buddies having a field day down there taking cool pictures of critters and treating my expensive Teric as a fancy bracelet.

Given your extensive dive schedule, I would posit that getting a cheaper backup computer with Buhlman that closely matched the Teric would be a better strategy than schlepping that D4 POS around the world with you.
 
Try this:
1. Take both your D5 & Shearwater (at the same conservatism setting you had before) to a light DECO dive # 1 (light DECO means you pass 1 or 2 minutes of DECO and that DECO disappears as you ascend slowly to the shallow),
2 Do a short surface interval, say for 45 minutes.
3. Go another light DECO dive #2 and now see how much penalty you incur on your D5 relative to your Shearwater.
If you do this 3 times in 1 day, the Suunto will give you really more penaltytime on the 3rd dive. But with 2 dives not. Also the next day, the first 2 dives are ok. The first one the Suunto gives you more time, the second dive, the differences are smaller, but then, Suunto is way more conservative. If the 3rd and 4th dive are within NDL, then there is no problem. If you do a 3 hour dive to 25m on ean32, and you have to swim quite a long way back at 10-12m, Suunto counts decotime up as penalty time, Shearwater counts down already.

I used my shearwater on 100/100 and the Suunto D5 for the photochampionships where deco was not allowed, and you had to show 1 computer after each dive. The dives were on air and 2 dives a day. Most times the Suunto give me 2-3 minutes extra NDL at around 25m diving on air, where the shearwater even with 100/100 showed 1-2 minutes deco. So then it was time to get up to not get disqualified.

But if you don't know how computers work, I cannot say suunto is a big problem for most divers. Only if you get it in the '505' modus. In my experience, Suunto give you earlier penalties and a '505' when doing long dives semi-technical dives with 10-20 minutes deco on backgas (a nitrox between 21 and 32% oxygen) with a maximum depth of 25-30m than with pure recreational dives that lasts only max 60 minutes within NDL and a max depth of 40m.
 
Suunto computers run a few different versions of RGBM. The D5 runs Fused RGBM 2. Set at its most liberal setting, it runs similarly to a Buhlmann GF high of 95. @Diving Dubai has many dives with his Eon Steel and Perdix and has posted extensively on this topic.
 
https://www.shearwater.com/products/teric/

Back
Top Bottom