Dive Computer Recommendation

[KevinNM]

The thing is, I don't feel my Suuntos "force" me to do or be anything; the default setting for conservatism (which is the most liberal of three "personal adjustment" settings, I believe) meshes just fine with the kind of diving I do.

You can also make it less conservative, though that is buried deep in the menus. The only time I was limited by NDL from doing a dive I wanted I was at 127 feet, and sufficiently narced that I didn't notice that I was out of NDL time. So as my objective is to dive yet avoid chamber rides, I increase the conservatism by one.

 

[industrious95]

I have an old Vytec from 2003 or so, still my main computer. The 3 button design is a lot easier for me to navigate then the 4 button design on the Vyper, but I'm learning. Getting into the controls for the dive modes still drives me crazy occasionally, and I have to do that before each dive to reset the AI code.

The Vyper does have a vastly better display, much better contrast, much easier to read in the water.

Hmmm - your Vyper has 4 buttons? Mine only has 3:

 

[Lorenzoid]

You can also make it less conservative, though that is buried deep in the menus. The only time I was limited by NDL from doing a dive I wanted I was at 127 feet, and sufficiently narced that I didn't notice that I was out of NDL time. So as my objective is to dive yet avoid chamber rides, I increase the conservatism by one.

Interesting. I haven't found that feature, and I've read the manual more than once and visited every menu as far as I know. I see in the manual for my D6 in section 5.95 where it describes "Personal adjustments," explaining that the default setting "P0" is for "ideal conditions," the "P1" setting is for "if conditions are more difficult, or any of the factors which tend to increase the possibility of DCI exist," and the "P2" setting is "the most conservative." Are you saying there is some other setting buried in some other menu? Where? I don't intend to mess with it, but I am interested to know if I overlooked something.

 

[stuartv]

The thing is, I don't feel my Suuntos "force" me to do or be anything.

If you have always ended your dive because you were down to your chosen limit on air, or because you were simply "done" and ready to get out, then that is great and I agree with you. I have read posts from other people where they got out before they really wanted to (and before they had to, based on air left) because they got within X minutes of the NDL according to their Suunto (where X is whatever personal limit they chose - obviously, could be 0). So, certainly, anyone like that, who has gotten out because of the amount of NDL time left has been "forced" to get out by their Suunto.

 

[Lorenzoid]

If you have always ended your dive because you were down to your chosen limit on air, or because you were simply "done" and ready to get out, then that is great and I agree with you.

That is indeed the case. For me and, I'm certain, many others. Look at my profile and see all the places in the world I have dived without feeling like the other people on the boat or in my group got more diving in than I did. People like me just don't post about it on SB, because to us it's a non-issue. Few people are going to post a report to the effect of "I had a great day today, and despite using a Suunto I did not get out of the water before the rest of the group." If someone's computer did not negatively impact their enjoyment of their day diving, they're simply not going to mention it, and you're never going to read about it. I suspect thousands of people dive every day with Suuntos, and the thought that they are being somehow cheated out of additional fun has never entered their minds.

But I, too, have seen those posts. I agree there is some minority of divers who will not be happy with a Suunto.

I have read posts from other people where they got out before they really wanted to (and before they had to, based on air left) because they got within X minutes of the NDL according to their Suunto (where X is whatever personal limit they chose - obviously, could be 0). So, certainly, anyone like that, who has gotten out because of the amount of NDL time left has been "forced" to get out by their Suunto.

Okay, I guess I read some subtle difference into it where there really is none--"forced to be more conservative" and "forced to get out" are, I suppose, the same thing. As I said, people who feel "forced to get out by their Suunto" should either get a new computer or take some other step to avoid that.

I suspect that in at least some of those instances where someone reported that their Suunto forced them to get out (or rather, computed less no-deco time than they anticipated), the diver could have avoided that by some means other than just having a different computer. A few minutes longer surface interval? One fewer repetitive dives during the day? A slower ascent rate? Doing the deepest dive of the day first? Suunto's algorithm seems to weight these things more heavily than some other computers. I suspect that some Suunto users don't think about these things--they haven't figured out how to dive in a way that maximizes their no-deco time. They just post reports complaining that Suunto is too conservative. I suppose there are some people who don't like the idea of having to think about "constraints" on their diving. For me, none of these are things I have to think about--they're just part of the way I normally dive. If someone is of the mindset that they don't want to think about constraints, then maybe they should get a true tech computer, which if they so choose they can set to be recklessly liberal and will not "force" ANY constraints upon them.

 

[stuartv]

If you have always ended your dive because you were down to your chosen limit on air, or because you were simply "done" and ready to get out, then that is great and I agree with you.

That is indeed the case.

I don't mean this to sound offensive, Lorenzoid. You have been very patient and helpful with me and I absolutely do not mean this in any way that you would find insulting. But, what you are saying makes me want to say that I am working on getting my SAC rate down and I hope to get to the point where EVERY dive I make ends either because I'm just "done" - seen everything I came to see and ready to get out - or because I'm up against my NDL - not because I've gotten down to my limit on air that's left. What you said is that every dive ends for you because you're either done or you're down to your air limit before you hit your NDL. I know you are an experienced diver, so I am surprised by that.

 

[Lorenzoid]

I don't mean this to sound offensive, Lorenzoid.

No worries. I've gotten used to your devil's advocate style of probing a question. And it's not like I own stock in Suunto--I couldn't give a rat's ass who uses what computer. Still, I have to admit that when I perceive Suunto-bashing it bothers me.

What you said is that every dive ends for you because you're either done or you're down to your air limit before you hit your NDL. I know you are an experienced diver, so I am surprised by that.

Except for the Bonaire and FL Keys trips and a smattering of other dives I've done, all of my diving has been done in an at least loosely DM-led group, as is common at resorts and such. Often, the DM wants us to surface more or less as a group. Sure, I could avoid those paternalistic dive ops and book with only those who let you dive to the limits of your computer/air, and sometimes I do. But I haven't yet encountered any dive op that cut off my dive so early as to leave me feeling cheated. I'm sure they exist, but I've been fortunate.

To the extent I am "experienced," that doesn't mean I am into diving deep wrecks or whatever. I've met divers who have thousands of dives racked up at destinations all over the world and have never done anything more aggressive than 20 mins. on the Spiegel Grove. So put me in that camp.

I can't remember the last time my air was the limiting factor--I have a good SAC rate. But sometimes it's my buddy's air. Or sometimes my buddy or I start getting chilly (even in the tropics this can happen when doing multiple dives per day), and maybe a combination of feeling slightly chilled and "we've seen what we came to see" prompts one of us to ask the other if we're ready to thumb the dive. Even in the Keys, where you're normally on your own, the dive briefing will typically admonish to "be back on the boat with 500 psi or in one hour, whichever is first." (And 50 min. is not an uncommon limit either.) Even in instances where the dive briefing does not include a hard time limit, I think etiquette requires not keeping everyone else waiting for TOO long on the boat. When the group includes a lot of inexperienced divers, I'm often the last one back on the boat--but maybe only 10 mins. after everyone else. In summary, for this kind of diving, the limiting factor on my bottom time is rarely my Suunto's NDL.

Like I said, people who do other types of diving may not want a Suunto. If I decide to get into more aggressive diving--maybe with a larger tank than an Al80--I'll probably get a Petrel and give deco considerations due thought. (As they say, "Every dive is a deco dive.") But for "fly the computer"-style vacation diving, a Suunto is more than sufficient for me and countless others.

 

[gfaith]

I don't mean this to sound offensive, Lorenzoid. You have been very patient and helpful with me and I absolutely do not mean this in any way that you would find insulting. But, what you are saying makes me want to say that I am working on getting my SAC rate down and I hope to get to the point where EVERY dive I make ends either because I'm just "done" - seen everything I came to see and ready to get out - or because I'm up against my NDL - not because I've gotten down to my limit on air that's left. What you said is that every dive ends for you because you're either done or you're down to your air limit before you hit your NDL. I know you are an experienced diver, so I am surprised by that.

Nice lofty goal there.. But if you usually dive a single AL80 and dive to the depth your are certified.. It might be difficult.. Of course, that is coming from a true Gas Hog..

 

[KevinNM]

Interesting. I haven't found that feature, and I've read the manual more than once and visited every menu as far as I know. I see in the manual for my D6 in section 5.95 where it describes "Personal adjustments," explaining that the default setting "P0" is for "ideal conditions," the "P1" setting is for "if conditions are more difficult, or any of the factors which tend to increase the possibility of DCI exist," and the "P2" setting is "the most conservative." Are you saying there is some other setting buried in some other menu? Where? I don't intend to mess with it, but I am interested to know if I overlooked something.

You adjust the RGBM parameters under the dive menu. IIRC, select dive, then [air or nitrox], then RGBM, then 50%. I have never done this, so I don't know how it actually impacts your diving.

"The Suunto Vyper Air also allows experienced divers who are willing to accept a
greater level of risk to adjust the RGBM model. The default setting is 100%, which
gives full RGBM effect. Suunto strongly advises you to use full RGBM effect. Statistic-
ally, very experienced divers have less incidents with DCI. The reason for this is un-
known, but it is possible that some level of physiological and/or psychological accom-
modation can take place when you are very experienced as a diver. Thus, for certain
divers and diving conditions, it may be desirable to set attenuated (50%) RGBM mode."

5.7.7. Setting the RGBM values
For certain divers and diving conditions, it may be desirable to set the attenuated
RGBM mode. The selection is displayed during the DIVE mode startup. The options
are full RGBM effects (100%), and attenuated RGBM (50%).

 

[Lorenzoid]

You adjust the RGBM parameters under the dive menu. IIRC, select dive, then [air or nitrox], then RGBM, then 50%.

Ah, I do now recall that there's an option to set RGBM to 50%. Thanks.

I vaguely recall reading a comment in some thread a long time ago from someone who had played around with these settings. I know my vague recollection is worth nothing, but I got the impression that changing the setting didn't make a huge difference as far as that person could tell.

I'm not inclined to mess with it. The default setting works fine for me.