Diving Shearwater with a Suunto buddy

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[Yeah there's some real winners here.]

I know on a NDL dive that I'm going to see my timer reach zero with most groups. That's a conservative setting, not real decompression. I stick with my group and watch my deco clear.

It's nobody else's buisness.

The benefit of tec is you get more freedom to plan real dives. Deco and depth ain't the boogy man.

The "you don't get to go as deep as them", bit gets really old.
 
Years ago I was using 50/70 for tech diving, and I didn't bother changing it when NDL diving. With a GF high of 70, my Shearwater was more conservative than a Suunto, especially on a first dive. I learned that diving with a friend with a Suunto Cobra. I would be regularly going into deco when he still had a little time. Because I am not an idiot, I knew that if I had taken a minute or two to change the GF high of my computers I would be fine and still be well within the true Buhlman NDL. Because I had stayed in tech mode, I would have a minute or two of required deco stop at the end of the dives, which would thoroughly clear before my friend was done with his 3-minute safety stop countdown.

As I said, I am not an idiot, so I knew I wasn't really in deco. However, ScubaBoard does have its share of idiots, so when I described the above practice years ago, one of them started a new thread about how I, as an instructor, was advocating going into decompression on NDL dives for people without proper training and equipment. He did not quote me--he just claimed I was advocating untrained divers going into deco. It was three days before I found the thread, three days of people calling me scum and saying I should be banned from ScubaBoard for advocating unsafe practices. When I found the thread, I linked to what I had actually written, and opinions changed--except, of course, for those who had left the thread after deciding I was a total jerk.
…aren’t forums fun?
 
As soon as you switch the Terric to Technical Mode to use the extra gauge reading spots, it'll select a more conservative algorithm.

On identical dives in Roatan, with dive buddies who didn't adjust their computers, my Terric was going into light deco on every dive, that cleared during the dive, due to the rolling hills kind of Roatan dives. It didn't do that in Rec mode.

I could adjust it to a less conservative setting, but there's no need. It seems safer, as is.

IIRC, you can select 2 or 3 presets, or dial in your own numbers. I'm on medium tech, I think. I'll check.

I haven’t actually looked into the settings at all. I had intended to just leave it on rec, for the most part.

I guess I should really learn more about these settings and what they mean. What is the default rec setting? It would probably make sense for me to set my shearwater conservatism close to my wife’s zoop novo. Maybe a hair more liberal.

I guess if I do upgrade I might as well just sell the zoop and convince the wife to get a tern tx.
 
I guess I should really learn more about these settings and what they mean. What is the default rec setting? It would probably make sense for me to set my shearwater conservatism close to my wife’s zoop novo. Maybe a hair more liberal.
When you are tech (decompression) diving, it is important to have computer settings as consistent as possible within a team., but it really isn't important in NDL diving. In both cases, you adjust to what is called (for want of a better term) the most "conservative" computer, but what that means for each is actually nearly opposite.

In NDL diving, when a team is diving together and one of the computers gets close to NDL, we say that is the most conservative computer, and it is time to ascend. If your buddy's computer controls the dive at that point, you ascend. It doesn't matter what your computer says, so you might as well leave it on default settings. The only advantage to having similar settings is that if one diver is not paying attention, the other one should be able to start the ascent process.

When you have to do decompression stops, it is quite different. In that case, the more conservative computer is the one telling you NOT to ascend. If your computer is telling you to ascend to your next decompression stop, and your buddy's is telling you to stay where you are, you have to resolve that conflict. In that case, the normal procedure is to stay down and wait for the other computer to allow the ascent. The computer that initially said to ascend should adjust to what is actually added bottom time. Things are much better if there is only a minute or two or three difference in those stops, and that is accomplished by matching settings.
 
I don’t mind my dive being controlled by my wife’s algo for now. I mainly want to upgrade to AI, and I like the design of the Teric. I could probably convince her to upgrade eventually to the tern or tern TX if we dive more often…but it sounds like keeping my zoop might be useless?

@Curious_George I’m curious why the downvote for this?
 
When you are tech (decompression) diving, it is important to have computer settings as consistent as possible within a team., but it really isn't important in NDL diving. In both cases, you adjust to what is called (for want of a better term) the most "conservative" computer, but what that means for each is actually nearly opposite.

In NDL diving, when a team is diving together and one of the computers gets close to NDL, we say that is the most conservative computer, and it is time to ascend. If your buddy's computer controls the dive at that point, you ascend. It doesn't matter what your computer says, so you might as well leave it on default settings. The only advantage to having similar settings is that if one diver is not paying attention, the other one should be able to start the ascent process.

When you have to do decompression stops, it is quite different. In that case, the more conservative computer is the one telling you NOT to ascend. If your computer is telling you to ascend to your next decompression stop, and your buddy's is telling you to stay where you are, you have to resolve that conflict. In that case, the normal procedure is to stay down and wait for the other computer to allow the ascent. The computer that initially said to ascend should adjust to what is actually added bottom time. Things are much better if there is only a minute or two or three difference in those stops, and that is accomplished by matching settings.

My wife will likely never do tech diving. As such, should I take from this that it won't really make any difference to our rec diving if I have a more liberal computer than hers? I will likely adjust the GF to give myself slightly more conservative values anyway, since I'm out of shape (unless round counts).
 
My wife will likely never do tech diving. As such, should I take from this that it won't really make any difference to our rec diving if I have a more conservative computer than hers? I will likely adjust the GF to give myself slightly more conservative values anyway, since I'm out of shape (unless round counts).
On an NDL dive, the team ascends when one of the computers says it is time to go up. It does not matter what the rest of the computers indicate.

Don't forget that if you are in an environment where this makes sense, like a sloping reef, you can do a multi-level dive. If the most conservative computer starts to get within range and everyone still has good gas levels, you can ascend until you get more NDL time remaining and continue to explore.
 
Hello. Most of this has been said in the post, but I’ll repeat since you ask.

Firstly, with your experience in the range of 0-24 dives, air integration or a $1200+ computer is an unneeded distraction. Great that you can afford it. I started with AI about the same time. Assuming here that you’ve already bought a reg set since it might be a hassle to add your transmitter to a different set of rental gear every day.

Unless you are the exception to normal new divers, time and money would be better spent working on perfecting buoyancy, trim, finning technique and air usage. Pay a friend or a DM to help you, rent some pool time, or just dive a lot more. Most men on AL80’s with your dive count run low on pressure before time; although again, perhaps you are the exception. From your questions, I’m not sure you really understand what "limited by my partner’s algo" means.

And here are the real reasons for my thumbs down (again, already covered by others):
1). You and your wife can easily dive different computers. Adjust the conservatism on one or both so the profiles are roughly the same. Some trial and error involved but what does it matter if there’s a minute or two difference in your no deco times? A new diver pushing deco limits is a really bad idea anyway so you should both ensure plenty of safety margin. And since you are travel diving, you may want to adjust the conservatism on your zoop as well and dive it as a backup. Teric reliability isn’t great, so the chance of needing a backup is not zero.

2). Also, consider that you or your spouse may actually need a more conservative profile, and focus on extending dive time could be risky. Any risk factors around age, physical fitness, ever checked for PFO? Ever ascended at above 30fps even for 10 feet during a dive? Ever have a few drinks the night before diving such that you might be dehydrated the next morning? Not saying any of these will get you bent, but they may add risk.

Just for a reality check; look at what the DMs are using on your dive trips. You’ll rarely see a shearwater outside of the US, and I guarantee they aren’t limiting anyone’s "algo". Don’t get too caught up in the bubble/echo chamber of Scubaboard. I think you are repeating what you hear here and need to learn/dive more and the correct decision will become obvious soon.

edit: realized my last paragraph may not have been clear. What I was trying to say is most DMs I’ve seen in the Caribbean use something other than a Shearwater (Suunto’s, Aqualungs, and similar are more common due to price I imagine) and I’ve never seen said DM‘s "algo" limiting anyone’s dive time.

happy diving, George
 
You’ll rarely see a shearwater outside of the US, and I guarantee they aren’t limiting anyone’s "algo".
People should not get the idea that a Shearwater magically gives them more bottom time than other computers. It doesn't. It is running the Bulmann algorithm that has been around for decades. Buhlmann himself has been dead for nearly 30 years. It is also running that algorithm with gradient factors that allow it to be set to a more conservative level. There are good reasons to use a Shearwater computer, but getting more bottom time is not one of them (except compared to Suunto).
 

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