'liberal dive computer' for live aboard style high frequency diving

[gopbroek]

This might help you...
View attachment 172116

It is a screenshot from someone else's site. I forgot who had done it so I'm sorry not to give proper credit. If someone remembers, pls add the link or the person's name.

I believe the chart was from the nice folks at Mission Scuba. They took it down awhile back because it was becoming dated, I contacted them and they sent me a copy. I like it because it gives similar algorithm groupings. I used it to match a couple of older used computers for a primary and backup set. I am currently using an Oceanic VEO 2.0 and a Sherwood Wisdom as a set and find that the algorithms track very close to each other. Recently I was diving aggressively in Cozumel with some days doing 4 dives with 5 hours bottom time. I was OK on NDL but I found if I did all Nitrox I would be hitting up on O2 limits, so I started doing any shallow dives with air. I would still recommend the VEO 2.0 (I like a 2 button model) as an excellent, lower priced unit. I picked up a used / 0 dive unit for under $150 on Ebay, currently they are selling at dive shops for around $300.

 

[KD8NPB]

Cochran EMC-20H offers the most aggressive algorithm out there.

Don't dive it on 0% conversatism unless you're an 18-25 year old Navy SEAL. lol.

 

[redacted]

I prefer the Uwatec algorithm. It has an excellent track record.

We always use Nitrox on live-aboards.

What recreational dive computer algorithms do not have "an excellent track record"?

 

[lv2dive]

Oceanic's algorithms are typically more liberal than Suunto's, especially for repetitive diving.

If you want to use a computer to tell you how much gas you have left, you can get one of the slightly older Oceanic Pro Plus 2's for under $400, and get a back up wrist Veo computer for around $150. Or you could get an analog gauge for $50, and get two Veo's for $300, and put one in a pocket. Unless you have a backup computer, if your primary computer craps out on you, the only way out of a 24-hour break in dives is if you have been logging each dive as you make it.

To whoever recommended a Cochran... Every day of the week and twice on Sunday, I'd buy a Shearwater Petrel before a Cochran but I think the OP said he was looking to spend 300-400. But that's just me.

(EDIT: I thought Cochrans were about 2k, looked them up it appears the standard version of the earlier-referenced model (EMC-20H) are running about 1200, so I corrected the above sentence since you can't buy 2 Petrel's for 1200)

 

[redacted]

Unless you have a backup computer, if your primary computer craps out on you, the only way out of a 24-hour break in dives is if you have been logging each dive as you make it.

That may be the recommended way out but it is not the only way out.

Computers tend to be reasonably reliable so my backup stays in my save-a-dive kit. If I have a computer failure, I will complete the dive in a reasonably conservative manner, take a good SI, switch to my backup, and continue diving using other available resources to keep it on the conservative side. Other available resources include a buddy's computer and dive tables. For a switch to tables, I will assume the most N2 loaded pressure group and then stay on the conservative side as I load the replacement computer for the rest of the dive day.

 

[KD8NPB]

(EDIT: I thought Cochrans were about 2k, looked them up it appears the standard version of the earlier-referenced model (EMC-20H) are running about 1200, so I corrected the above sentence since you can't buy 2 Petrel's for 1200)

I picked up mine for like $300 used. There's a lot of them on the market since they're quite durable and they've been in production for about 20 years.

 

[scubadada]

My first computer, a Cochran, was easily the most liberal. I switched to Oceanic DSAT algorithm in 2001 and have stayed with it since. I have nearly a thousand dives on this algorithm and will not be changing. I dive a VT3 primary and a Geo2 and SPG backup. The Geo2 is on sale at LeisurePro for $279. Perhaps they're going to upgrade or discontinue this model, I like it.

Good diving, Craig

 

[halocline]

I prefer the Uwatec algorithm. It has an excellent track record.

Nice one, beav, but what you 'forgot' to mention is that ALL dive computer algorithms have an excellent safety record and there is ZERO-ZIP-NADA statistical evidence that one is any safer than another.

It would have been a bit more forth coming if you said something like "I prefer the Uwatec algorithm. It has an excellent track record of making me money through sales."

To the OP, the aeris XR1 or XR2 is a good basic reasonably priced dive computer that does everything you need, and aeris customer service has always been very good in my experience.

For safety, the best thing you could do by far is to learn a bit about DCS incidence, the associated factors involved, and a bit of deco-model theory, like the concept of multiple tissue compartments. Not a lot, just enough so you get an idea of how various dive behaviors seem to present greater risks, and how some behaviors seem to mitigate risks. Two good examples are good hydration practices before and after diving, and extended safety stops at 10-15 feet. Long safety stops are thought to be especially efficient at off-gassing in recreational settings. Then you can control your own profiles and dive behavior from a standpoint of greater understanding of the physiology at work.

 

[beaverdivers]

Nice one, beav, but what you 'forgot' to mention is that ALL dive computer algorithms have an excellent safety record and there is ZERO-ZIP-NADA statistical evidence that one is any safer than another.

I have had a much better experience with Uwatec dive computers than any other dive computer that I have used. Those computers include Cochran, EDGE, Oceanic, Suunto & the first Scubapro dive computers. I have been satisfied with Uwatec for twenty years.

The new computers don't have a very long track record.

If all dive computers have such an excellent safety record, then why does anyone bother with dive tables?

 

[KeithG]

I assume you have read THIS thread on algorithms.

IME it is not the specific computer- rather the types of profiles that the individual makes that 'forces' them to ascend earlier than their buddy.

There are divers that always dive at the maximum depths for a dive No one computer will make or break the dive- all will 'force' them to come up sooner rather than later. I like to cruise at a shallower depth and only descend when it gets interesting.

I have found older Uwatec Pro's to be aggressive. Be very careful with final ascents as they do have a reputation as a 'bend and mend' computer.

Agreed. Liberal vs convervative does not really matter much when doing 5 one hour+ dives each day.

You need to adjust your profile, not your computer.

An interesting excercise is to drag out your tables and workout the worst case square profile for the day. Assume every dive is the same depth, spread your 5 dives from 8am to 7pm and see just how deep you can go.

Not as deep as you thought.