Looking for a more aggressive computer algorithm.

[redacted]

Check the web page, the data plus is really old, the VEO 180 and 250 are now "old"

The newest computers they are coming out with have BOTH algorithms available. The diver can select which one they want to use. The Z+ is newly developed by Oceanic, as in within the last year.

Yes, I was pretty sure we had different concepts of "old". Actually, my computer is new compared to my regulators.

 

[wedivebc]

Are you diving nitrox? Are you diving at least rule of thirds?
.

Why would he want to dive rule of thirds?

 

[fppf]

It depends on the dive of course.

But even on a recreational dive to those depths I follow thirds. Most times at those depths I will be diving off a boat, many times there will be surface currents. Returning to the line and making controlled accents with safety stops is high on my list. Direct accents can put you a long way from the boat after a controlled accent and safety stops.

But in a real case of gas planing even thirds is not enough, this has been beaten other places. On a recreational profile I find it much better practice then rock bottom 500 PSI.

 

[scubafanatic]

First, I disagree with those saying "there's only a few minutes difference" between algorithms. Obviously they've never run a late model Suunto and an Oceanic together on the same dive. (FWIW, I used to dive a Suunto Companion that was pretty aggressive for an air computer but that was 15 years ago)

But I will say, there's not a large difference between the Prime and say a VEO 250.

I agree 100% here.....I use Oceanics (DataMax Pro Plus II's) and Cochrans.....and have had the misfortune of diving with Sunnto users......I even gave a free Pro Plus II to a dive buddy as her Sunnto was driving both of us crazy......and I've dove with others with Sunntos, and I'm always blown away by the differences between them...Sunntos are WAY conservative....you couldn't even give me a free Sunnto to dive...I'd E-Bay it ASAP or make a tiny artificial reef out of it!

 

[djanni]

Are there differences between them in terms of NDL? Sure. My point was that the likelihood that the difference will appreciably change the way the OP and his wife will dive is pretty slim.

I dive a Vytec DS, my buddy dives an Oceanic Datamask. We both have decent SAC rates. We've done literally hundreds of dives together all over the world; everything from 90min shore dives in Bonaire to ~160' wall dives in Caymans to 100' deep wreck penetrations in the Red Sea. In all that time we've never had a single dive where my Suunto wanted to send me up significantly earlier than his Oceanic.

I'd say that on the average "single AL80 dive" we're coming up after 45-60min with >750psi simply because "we're done with the dive."

How much time is "significantly early?" Based on my experience with Oceanic, especially when another diver is using a Sunnto, the Oceanic is around 10 minutes more liberal. I think Oceanic is even more liberal on multiple dives too.

Based on your experience with your buddy's Oceanic maybe the difference is how he has it set up. Maybe he set it up to be more conservative to compensate for your Sunnto. Just a guess.

 

[deepstops]

Are there differences between them in terms of NDL? Sure. My point was that the likelihood that the difference will appreciably change the way the OP and his wife will dive is pretty slim.

I dive a Vytec DS, my buddy dives an Oceanic Datamask. We both have decent SAC rates. We've done literally hundreds of dives together all over the world; everything from 90min shore dives in Bonaire to ~160' wall dives in Caymans to 100' deep wreck penetrations in the Red Sea. In all that time we've never had a single dive where my Suunto wanted to send me up significantly earlier than his Oceanic.

I'd say that on the average "single AL80 dive" we're coming up after 45-60min with >750psi simply because "we're done with the dive."

See post 24

And yes, I'm talking about AL80 diving in Cozumel where I'm showing 14 minutes of BT and my friends Vyper is showing 20 minutes of DECO. This happened on the 2nd dive of the day on the 2nd day of the vacation (5th dive overall), profiles within a few feet of each other, same mixes, nothing wrong with the Vyper's settings.
Yes, there can be big differences, especially if you "violate" Suunto's one hour minimum SI (which we found out after some research).

 

[RJP]

How much time is "significantly early?" Based on my experience with Oceanic, especially when another diver is using a Sunnto, the Oceanic is around 10 minutes more liberal. I think Oceanic is even more liberal on multiple dives too.

I suppose I chose my words somewhat inartfully. What I meant to convey was that we've never specifically ended a dive because my computer wanted to send us up before his did.

As to the idea that the Oceanic is "10 minutes more liberal" that assertion doesn't really mean anything without knowing the profile of the dive in question. An extra 10 min added to a dive with 20min of NDL is significant. (+50%) An extra 10min on a dive with 95min of NDL is not really all that meaningful. (~10%)

Based on your experience with your buddy's Oceanic maybe the difference is how he has it set up. Maybe he set it up to be more conservative to compensate for your Sunnto. Just a guess.

Good question, will have to look into that.

However, knowing my buddy...he would not have passed up a chance to bust my b@lls if that were the case.



Note to buddy: Dave, if you come upon this thread please do let us know whether you've got the conservatism on your Oceanic jacked up.

I guess the main point is that we're able to do the dives we want to do, for as long as we want to do them - and we're not exactly "shy, retiring types" when it comes to dive planning. Beyond that, we'll often do as many as 5 dives a day on vacation and have never seen the type of "repetitive dive penalties" that others mention.

I have no doubt that if - for whatever inconceivable reason - we decided to plan a dive where the objective was to "max out NDL for no other reason than to do so" that my computer would be the rate limiting factor.

In the real world however, as I just mentioned in another thread, I've never ended a 90min dive thinking "I don't feel any microbubbles - damn piece of Finnish cr@p!"

 

[RJP]

See post 24

And yes, I'm talking about AL80 diving in Cozumel where I'm showing 14 minutes of BT and my friends Vyper is showing 20 minutes of DECO. This happened on the 2nd dive of the day on the 2nd day of the vacation (5th dive overall), profiles within a few feet of each other, same mixes, nothing wrong with the Vyper's settings.

I must have a defective Suunto then. When I was in Truk earlier this year I was doing 4-5 dives a day (for 17 days in a row) and never noticed my NDLs being significantly impacted on subsequent dives. This is compared to both my V-Planner "planned" schedules and the computers of those with whom I was diving - on NDL and planned deco dives.

Yes, there can be big differences, especially if you "violate" Suunto's one hour minimum SI (which we found out after some research).

Well, yeah...if you VIOLATE your computer it's gonna ding ya!



What other violations did your buddy have? I think Suunto's will complain if you do significant saw-tooth profiles, ascend from deep to moderate depths too quickly, or bounce.

 

[TSandM]

First off, I think it's important to be sure that the OP understands that nothing is going to change his nitrogen loading for a given dive . . . computers calculate allowable time at depth based on the algorithms and assumptions they were programmed with, but the nitrogen loading remains the same. Since no one knows precisely what the kinetics of inert gas are within any given human body on a given dive, ALL computers are attempts to predict the likelihood of DCS from a given profile, and keep that probability within a given, low number.

There is nothing that requires that you respect the NDLs of your computer, if you don't trust what it says, although many computers will insist that you do ridiculous amounts of deco for minor violations, and will get cranky if you decide to dive again. You can solve that by putting your computer into gauge mode and running a mental set of tables, or running decompression software (which is often more generous, but was not really designed for NDL dives).

You can also get more bottom time by using Nitrox.

But in the end, if your gas consumption is good and your topography is such that deeper dives are attractive, you may well end up getting some training that will allow you to enter into mandatory decompression and deal with it. Going over NDLs isn't a disaster, if you have planned for it and know what you are doing.

 

[gcbryan]

Does anyone else find it odd that Oceanic came up with the Dual Algorithm thing and then used DSAT and ZHL-16 (c).

I would expect it would be traditional dissolved gas (ZHL-16 or DSAT) vs dual phase (VPM-B or RGBM).

Instead it seems they are billing DSAT as liberal and ZHL-16 as conservative.

On top of that you can change the conservative settings of each of those algorithms.

It's kind of a funny mix isn't it?

You would think they would either use two really different algorithms or just use one liberal algorithm and add conservative settings and just call it a day.