Considering new nitrox wrist computer. Thinking about Aeris XR-2.

[Dirty-Dog]

My wife dives an XR-1NX, and I use one as a backup. The differences between the XR-1NX and XR-2 are trivial. The XR-2 has a a PC download port. That's about it...

The Aeris is easy to operate, easy to read, reasonably conservative, and inexpensive. The battery is easily user replaced. We've had zero issues with ours.

There are certainly dive computers with more features (and higher prices) but for a simple, basic computer, the XR-2 should be a fine choice.

 

[irishsquid]

Personally, the liberalism never bothered me. Pay attention to it and just don't run it to the edge and you should be "fine". (Everyone is different) You can set the alarm at any level if you don't monitor as often as you should.

 

[Jim Lapenta]

I would never allow a computer to regulate my dive plan anyway. The computer is the back up. The Oceanic algorithm is fine. If you want real conservatism dive tables and build up to using a computer. I do not recommend computers for my new OW students. Concentrate on planning, using tables, and diving profiles you actually plan and follow. When this is second nature go for the computer to extend your dives and get a little more bottom time out of a dive.

 

[irishsquid]

I would never allow a computer to regulate my dive plan anyway. The computer is the back up. The Oceanic algorithm is fine. If you want real conservatism dive tables and build up to using a computer. I do not recommend computers for my new OW students. Concentrate on planning, using tables, and diving profiles you actually plan and follow. When this is second nature go for the computer to extend your dives and get a little more bottom time out of a dive.

This what I actually did my first year (50 or so dives). I didn't own a computer yet. I still run my tables before and after a dive just for comparisons. I do cheat my original table plan some as I'm not doing true "square" profiles. I start my dive at the max depth for the planned time, with ample time allowed to sight-see on my return.

 

[boat sju]

My wife dives an XR-1NX, and I use one as a backup. The differences between the XR-1NX and XR-2 are trivial. The XR-2 has a a PC download port. That's about it...

The Aeris is easy to operate, easy to read, reasonably conservative, and inexpensive. The battery is easily user replaced. We've had zero issues with ours.

There are certainly dive computers with more features (and higher prices) but for a simple, basic computer, the XR-2 should be a fine choice.

I've had an XR-1 for 5 years and would pretty much say the same thing as Dirty-Dog. Mine seems to burn through batteries quicker than I'd like though. That was a common complaint back around 2007. Dirty Dog - I'm curious as to how yours' are on batteries - being newer models?

As for being liberal: End your dives back in the "green", you can make any computer as conservative as you like.

 

[Dirty-Dog]

I've had an XR-1 for 5 years and would pretty much say the same thing as Dirty-Dog. Mine seems to burn through batteries quicker than I'd like though. That was a common complaint back around 2007. Dirty Dog - I'm curious as to how yours' are on batteries - being newer models?

As for being liberal: End your dives back in the "green", you can make any computer as conservative as you like.

Um, well... I'll let you know when I change them for the first time. We've had them for about 18 months. They've spent about 66 hours under water, plus the associated SI/No-Fly times.
I had heard the battery concerns, so I bought new batteries after our first two trips. Took another trip in May. Got another one in Dec. So far so good...

 

[boat sju]

We've had them for about 18 months. They've spent about 66 hours under water, plus the associated SI/No-Fly times.

Sounds like they've solved the battery issue then. Maybe it's time to replace my xr-1 with an xr-1nx since I'm planning to go to Bonaire in January anyway. On the other hand, I'm getting pretty good at swapping batteries.

 

[scubadada]

The other issue is that some of the older Oceanics used a very liberal algorithm. The liberal algorithm is now out of favor. Their newer computers allow a choice of algorithms. I dove with three computers: an old Oceanic Prodigy, a Suunto Vyper and Galileo Sol, and the Oceanic is so much more liberal I would not be comfortable following it as my main computer.

Adam

There is a trend towards more conservatism. Oceanic was the king of the liberal algorithm and now provides a second more conservative algorithm which is closer to Suunto's. Other brands like Mares and Uwatec and of course Suunto are also conservative. My statement is also based on the reports of DCS after diving within the rules of the dive computer, which suggest insufficient safety margin in the algorithm.

If you do dive one of the older liberal computers it's a good idea IMO to stay away from the deco limits at the end of the dive. For example in my Prodigy you can make a point of always exiting the dive with the nitrogen loading graph in the green zone. It's a way of increasing the safety margin.

Hi Adam,

The Pelagic DSAT algorithm is out of favor with whom other than you? Do you have some data to backup your assertion that the rate of DCS is higher with this algorithm than others?

 

[Hatul]

Hi Adam,

The Pelagic DSAT algorithm is out of favor with whom other than you? Do you have some data to backup your assertion that the rate of DCS is higher is higher with this algorithm than others?

DSAT was the older Oceanic algorithm and as you know all their newer computers now provide a second more conservative choice. I'm not aware of any studies on DCS accidents vs algorithm. It would be quite difficult to perform such a study on rare events that occur within the rules of the computer. But absence of evidence is not evidence of absence. It's clear that if you dive close to the limits, a more conservative computer is safer. It has to because the conservative computer will allow less nitrogen loading or slower unloading or both.

Lets consider a dive to the non deco limit by a liberal computer. For the same dive a more conservative computer will prescribe a deco stop by definition, so the guy who dives the latter comes up slower, and offgasses more before surfacing. Unless you totally reject decompression theory you can't deny that the diver with more nitrogen at surface is at more risk for DCS. There is just no way around it.

It's tempting to choose a computer with the liberal algorithm because you get more bottom time, but what you don't see or feel is that you're cutting you margin of safety. You don't feel it until you get hit. IMO

Adam

 

[NCadiver]

My wife dives an XR-1NX, and I use one as a backup. The differences between the XR-1NX and XR-2 are trivial. The XR-2 has a a PC download port. That's about it...

The Aeris is easy to operate, easy to read, reasonably conservative, and inexpensive. The battery is easily user replaced. We've had zero issues with ours.

There are certainly dive computers with more features (and higher prices) but for a simple, basic computer, the XR-2 should be a fine choice.

Actually it have couple of more features backlight and audible alarm.