Watch with Similar Algorithm for Partner (and buddy)

[ross9]

On the upside you can steal it to do tec because in the future you can upgrade it to Trimix which you can't with the Garmin

I thought I'd read the Garmin can do trimix?

In the future your Garmin might not be the computer you want because it's not really a Technical computer, and in the future there will be new models from the established manufacturers.

So you could go with your Garmin and suck it up and buy an OSTC or you could drop the Garmin as a Dive computer option and maybe buy a pair of Computers in the £250 - £300 range.

It's not a bad idea. Maybe I could live with my existing Garmin Fenix for sport and a cheaper dive computer... Food for thought!

 

[Diving Dubai]

It's not a bad idea. Maybe I could live with my existing Garmin Fenix for sport and a cheaper dive computer... Food for thought!

There's no right answer, you have to go with whats right for you and what's affordable.

When you're ready for Tec, there may be different options around, and thus you might regret having spent a lot of money now. O
n the other hand, if you have an entry level computer, it can always be used as a backup or spare. My wife and I used Cressi Leonardo's for the first year/150 dives, before we chose Eon Steels because we wanted the colour screens.

We still have the Cressi's and change the batteries each year, and chuck them in our BCD when we go on vacation, just in case something happens to our main computers. So that initial expenditure isn't wasted (and frankly by the time you get into Tec the price of another Dive computer is insignificant with the rest of the money you're spending.

Good luck on which ever choice you make

 

[scubadada]

There's no right answer, you have to go with whats right for you and what's affordable.

When you're ready for Tec, there may be different options around, and thus you might regret having spent a lot of money now. O
n the other hand, if you have an entry level computer, it can always be used as a backup or spare. My wife and I used Cressi Leonardo's for the first year/150 dives, before we chose Eon Steels because we wanted the colour screens.

We still have the Cressi's and change the batteries each year, and chuck them in our BCD when we go on vacation, just in case something happens to our main computers. So that initial expenditure isn't wasted (and frankly by the time you get into Tec the price of another Dive computer is insignificant with the rest of the money you're spending.

Good luck on which ever choice you make

I just can't believe that your Cressi computers do not go into violation gauge mode unless your profiles are extremely conservative.

 

[dmaziuk]

Budget probably tops out around £300-350.

You should be able to get seac guru for 350-400 quid but they seem to get a lot of "stuck button"/"button fell out" reviews here, so... but it's the only usable ZH-L16 one in your price range ATM.

 

[Diving Dubai]

I just can't believe that your Cressi computers do not go into violation gauge mode unless your profiles are extremely conservative.

On a standard (vacation) live aboard, with 3 dives a day (our preference) there's nothing difficult. Profiles are "conservative" (no deco) and governed by dive time and gas time (respecting rock bottom values on an Al 80) with long SI. Most guides are using some flavour of RGBM, so no I don't put my Cressi's into violation.

When making a long series of repetitive dives as you typically do on vacation, we choose to err on the side of more conservatism anyway than we typically do on our bi weekly local dives

 

[rongoodman]

Out of interest, why is this particular algorithm only paired with more expensive computers?

My best guess would be that cheaper recreational computers just didn't have the computational power to run it when they were choosing which algorithm to use. It was a big deal when the Liquivison X1 came out in 2007 with the power to run VPM. Buhlmann GF was added as an option not too long after that. Similarly, Suunto only claims to provide a full implementation of RGBM on some of their more expensive models, although it's a little hard to tell because of the various proprietary model names which they use.

 

[dmaziuk]

My best guess would be that cheaper recreational computers just didn't have the computational power to run it when they were choosing which algorithm to use.

This is true of bubble models but not of ZH-L. ZH-L's really quite simple. It was not designed for no-stop diving, like DSAT, it has no built-in fudge factors for repetitive diving like RGBM nor the bubble radius magic to penalize for "bad" profiles and excessive ascent rates like RGBM/VPM. SB Shearwater fan club considers this "a feature", if I were designing a computer for OW cluebies I'd consider it more of a liability.

 

[jgttrey]

I think the need to match algorithms for recreational diving is vastly overstated. Since you're thinking about tec, the MK1 is a good choice for you, but you say she's not interested in tec. She doesn't need that kind of capability.

Algorithm matching is much more important for tec diving because it is very desirable for buddy teams to have similar decompression schedules, both time and depth. It isn't a big deal in recreational diving where you are only concerned about no stop time. Two reasons:

First, you can easily program your MK1 to come out roughly the same.

Second, who really cares? Just ascend when the first computer gets close to NDL. It's gonna be close if you've programmed your GF high somewhere around 90. You're still going to get a decent dive provided you both are using reasonable settings.

Think about it this way: Every time you dive with a guide, it's virtually certain that members of the group have different DCs with different algorithms. The guide's NDL, even if he/she had the same computer will be different because of prior dives and nitrogen loading (or artificially shortened because the guide has more dives in the afternoon. Is having different algorithms in that context some huge problem? No.

I dive Shearwaters at 50/80 GF. My wife and kids use Oceanics running DSAT. It's just not a problem. If you planned to push limits and do 5 dives a day on liveaboards and ride the NDL the whole time (not best practice anyway) then maybe there'd be slightly more need, but it just isn't that big a deal.

Personally, since your partner isn't on a path to need a "tech" computer, which is more expensive anyway, you should focus on the computer with the best form factor and user interface for her. That is far more important to her dive happiness than trying to find one that runs ZHL so you can match it exactly to your MK1.

 

[ATJ]

I have been diving with a Garmin Descent Mk1 for around 18 months on GF 40/85 (medium conservatism). I also have a Shearwater Perdix AI (also running GF 40/85) and an old Oceanic Atom 3.0. I found the Oceanic on PZ+ and Conservatism Off runs pretty close to the Perdix and the Mk1 (unless you drift into Deco and it has much higher Deco commitment).

Other Oceanics have the same available algorithms.

If you run other gas factors on the Mk1 you might have to play a bit.

 

[ross9]

Thanks all for the input.

I think I'm now tossing up between an Mk1 for myself and a geo 4 for her, or just geo 4s for us both. If/when I progress to tec I'll need a backup computer. And if that's two years from now seems like it makes more sense to pick up a tec computer later when the technology is further advanced.

Next trip is in six weeks so I'll have to decide before then!