Different algorithms for buddys...

[burnerking]

Hi

New to the site so firstly, hello! I've been reading and reading this forum and used the search function to find my answer but I'm going round in circles.

I just bought a dive computer (Mares Puck). It's going to be my girlfriend's as I'm looking for something else - maybe a Veo 3.

Anyway, the Mares Puck uses the RGBM algorithm. Do I need to get a computer with the same algorithm or similar? Is it a big issue if we have different algorithms? I know some are more liberal than others... I think the RGBM is most conservative?

We're both recreational divers with AOW cert.

Thank you in advance.

 

[Tortuga68]

Do I need to get a computer with the same algorithm or similar? Is it a big issue if we have different algorithms?

Short answer is no. When one of you gets close to NDL, you both ascend. Simple

 

[muddiver]

Even if you both have computers that are "based" on the same algorithm, they probably don't computed it the exact same way. It's like comparing Microsoft Excel to Lotus 1-2-3. They do the same thing running on the Microsoft operating system, but they are completely different strings of computer code.

Having the same brand and model of computer for the both of you would be the only way to get close to the two of you being on the same dive table, without using a table. Then is will depend on you dive profiles. Either way you both ascend when one or the other hits their No Decompression Limit.

 

[Cave Diver]

Do I need to get a computer with the same algorithm or similar? Is it a big issue if we have different algorithms?

No, but there needs to be some pre-dive communication on what your plan is going to be. Hopefully it includes starting your ascent at a predetermined point, rather than just "riding" the curve of the NDL up.

Most computers have a plan mode, where you can put in the max expected depth and it will give you a time limit. Discuss the time & gas supply you want to leave the bottom with ahead of time then follow that on your dive.

 

[Pauly854]

My son and I had been strictly diving RDP tables, but I recently got a computer...but he doesn't have one(yet). I still have him do his tables and calculate his RAT, and we never come close to decompression limits. I'm sure it is recommended for him to stick to his tables if we ever get close to limits, but it would certainly give me more bottom time than him. What do others do when diving with a buddy without a computer? I hate to have him go by MY computer, but it would prolong his bottom time. Opinions?

 

[ianr33]

I hate to have him go by MY computer, but it would prolong his bottom time. Opinions?

Unless you really know what you are doing that is a BAD idea! Either stick with the tables or get him a cheap computer.

 

[Pauly854]

Unless you really know what you are doing that is a BAD idea! Either stick with the tables or get him a cheap computer.

Pretty much what I figured, and I vaguely remember something to that effect in my OW class. But that was 16 years ago, and was never an issue since I've had a computer for 6 months (yeah, I'm a little slow). Like I said, we stay well clear of limits, so it hasn't been an issue...but it is sure to come up some day. Thanks

 

[Dirty-Dog]

It's a fact of life that different models will give different answers. Even if you are both wearing identical computers, your dive profiles will vary slightly, and when you consider the possibility that you might have the sampling rates set differently, it gets even more complicated.
The simple, safe, and consensus answer is that you dive the most conservative profile. That means that when one computer (or table, if one of you is diving tables) says it's time to thumb the dive, you all head for the surface.

 

[ianr33]

That means that when one computer (or table, if one of you is diving tables) says it's time to thumb the dive, you all head for the surface.

Agreed, but would point out you don't need to go all the way to the surface. Anything less than 30 feet is good enough (actually better) .
If diving tables there is nothing wrong with doing your 19 minutes at 100 feet,slowly ascending to ,say,25 feet and staying there for a couple of hours if you have the gas. Essentially its just a really long safety stop. (The NDL at 30 feet is DAYS)

This tends to be a more attractive option somewhere such as Bonaire rather than a northern quarry!

 

[DiveNav]

....... Do I need to get a computer with the same algorithm or similar? ......

The Veo 3.0 has a dual algorithm, and according to Oceanic it could be programmed as "liberal", "middle of the road" or "conservative".
As per the image below, its "conservative" mode is even more conservative than the Puck Air.

We have online classes for both the Puck and the Veo 3.0.

Alberto (aka eDiver)