Buying first computer Suunto Zoop, Cressi Giotto, or Oceanic Geo 2.0 ?

[dmaziuk]

If the computer is suggesting a 10-15 minute safety stop, this sounds like a weird interface design:
- if it is required by the calculations, display the "required" (aka "deco") icon,
- if it is not required, and diver can surface at any point without any penalty, then why show the 10-15 minute countdown? Why not 5, or 50?

It's what Ken said: if it had 2 M-values, one for "safe enough" and another for "really really safe", and the 10-15 minute safety stop was to clear the 2nd one...

 

[scubadada]

If the computer is suggesting a 10-15 minute safety stop, this sounds like a weird interface design:
- if it is required by the calculations, display the "required" (aka "deco") icon,
- if it is not required, and diver can surface at any point without any penalty, then why show the 10-15 minute countdown? Why not 5, or 50?

It's what Ken said: if it had 2 M-values, one for "safe enough" and another for "really really safe", and the 10-15 minute safety stop was to clear the 2nd one...

I don't think any computer works this way. The manual that @ScubaJill provided is very straightforward and similar to all the manuals I have perused for many brands of computer. The Cressi has a preset 3 minute safety stop. Several of us have concluded that the 10-15 minute shallow stops are most likely deco. The easiest way to end the confusion here would be to have Jill post the downloaded profiles from the implicated Cozumel dives. As this is a thread posted by a beginning diver in search of a 1st computer, I think the least we can do is to supply accurate, helpful information. If Cressi has a variable, optional safety stop of up to 15 minutes, we will all learn something.

 

[divinh]

I've done deco dives with the Giotto. It was planned because we knew it was our third deep dive of the day. The DM told us to signal her when we reached 5 min deco obligation, which is clearly indicated by the work DECO and a counter that went up, which previously counted down. We proceeded to the safety stop depth and waited it out, until everyone's computer cleared.

From my understanding, the Giotto also has a Deep Stop option, which will tell you to do a deco stop at a depth deeper than the normal safety stop. If you were to skip it at the depth indicated, it would allow you to satisfy the obligation at safety stop depth or slowly swim upward and count that as the same.

 

[caruso]

Zoop computers are very conservative. Quite often on a dive boat where there's a bunch of divers doing wrecks, the divers with Zoops are first back on the boat by at least 10 minutes, with plenty of gas remaining in their tanks. And it's not like all those other divers with the more generous computer algorithms are getting bent.

 

[KenGordon]

Zoop computers are very conservative. Quite often on a dive boat where there's a bunch of divers doing wrecks, the divers with Zoops are first back on the boat by at least 10 minutes, with plenty of gas remaining in their tanks. And it's not like all those other divers with the more generous computer algorithms are getting bent.

Conservative compared to some ideal you know?

People do get bent, people even get bent diving Suuntos.

 

[caruso]

Conservative compared to some ideal you know?

Extremely conservative compared to most other dive computers.

 

[outofofficebrb]

Zoop computers are very conservative. Quite often on a dive boat where there's a bunch of divers doing wrecks, the divers with Zoops are first back on the boat by at least 10 minutes, with plenty of gas remaining in their tanks. And it's not like all those other divers with the more generous computer algorithms are getting bent.

Extremely conservative compared to most other dive computers.

I dived a Suunto for about 130 dives - both a primary and a backup. My partner still dives his set but I have dived the last 50-60 dives on a Shearwater primary with an Oceanic (DSAT) backup. I have been able to observe both side by side diving the same profiles on repetitive dives (4-5 dives a day over 5-6 days) as my partner is also my buddy. On medium conservative setting for the Shearwater and as liberal as the Suunto will go (A0P0), it is quite close to the Suunto and nothing drastic. On low conservative setting on the Shearwater, the difference is quite noticeable. We were on dive 16 of the week and on that particular dive, max depth was 89 feet, average depth was 63 feet. Dive time was 39 minutes. We had enough air to keep going, but not enough NDL time for my partner. It was not an option to ascend shallower and keep diving. It was a wreck and it was all or nothing, no reef. There was a difference in NDL of about 20-25 minutes. So, yes, it can be conservative compared to other computers but in my case, it also depended on what conservative setting/GF it is set to. Some are as conservative if not the same as the Suunto depending on the settings.

 

[aquacat8]

Do you like to freedive or snorkle? I wanted a Geo2 because it also is a freediving watch... however it does not log those dives though you can look at the last one. I think I need the cable if I want to see my older freedive data, but on the fly it is decent enough, giving depth, time, and SI of current and last dive. If you liked the “skin diving” portion of your cert class this might be a consideration. Never freedive after Scuba. However if you jump in the pool forgetting to take it out of normal (Scuba) mode, after a short SI ( I think 5-10 mins) it allows you to switch to free.

 

[KenGordon]

Extremely conservative compared to most other dive computers.

Most? Extremely? Have you used one? I regularly do and I also use Shearwaters set to 50/85 or 80. I’d only use a GF95 in an emergency and generally find the Suuntos and Shearwater more or less agree.

The example above is interesting because it involves repetitive diving. Repetitive diving is a known provocation. Is it ‘extreme’ to take account of that?

Most? A whole bunch of manufactures use similar algorithms to the Suunto. They all took advice from the same bloke when he was fashionable. In this list this is Cressi.

The outlier is Oceanic. I recently tried to buy one but failed. They are no longer available new and the secondhand one died. Before it’s dive it seemed to give the same no stop time as all the other computers. It was a deep single dive though.

 

[caruso]

Most? Extremely? Have you used one?.

I am basing my posts about the Suunto Zoop strictly on the conversation I had with the crew aboard an Ocean Divers boat in Key Largo last year before a dive and during a surface interval following a triple wreck dive on the Duane, Bibb and Speigel Grove wrecks, which started because I heard him say to another crew member "those 2 will be back at least 10 minutes before everyone else, they have Zoops". Cutting a ~25 minute dive short by 10 minutes is very significant and after looking around and expecting to see a sea scooter or something, I asked him what a Zoop was and got a very thorough, detailed explanation of how conservative Zoop computers are, and how it's become a matter of course to expect divers with Zoops to be back on the boat before everyone else.

That was enough for me to know I'd never, ever get one. My Oceanic has provided me with generous dive times for almost 400 dives and I've never gotten bent. To settle for excessively shorter dives for no other good reason than an arbitrarily conservative algorithm is a waste of good dive time.