Now it's time to choose a wrist computer.

[Gandalf-the-Diver]

I have a suunto zoop novo as my backup computer, which is RGBM and famously conservative. I have my peregrine adjusted to GFHi = 75% and it is actually _more_ conservative than the Suunto most of the time. For liveaboard diving, where you do lots of dives but limited to 1h, that has not been an issue for me, although I tend to be a bit more conservative about depth than some people.

If you want to dive in deeper to the dispute, RGBM is based on "bubble models" which are somewhat discredited among decompression researchers. Or at least that's the consensus around here.

I too use a Zoop Novo as backup to my Peregrine. I just changed the conservatism setting on my Peregrine to low. My Shearwater was putting me into deco while the Zoop had tons of NDL time.

 

[waterone]

Backup computer? Are you taking about a backup that you keep in your dive bag incase your primary goes down or do you dive with two computers?

Many people dive with two computers. I have never had one fail but I run solo a bit.
I run a mk1 and mk2i most of the time and sometimes the mk2 and a Teric.

 

[inquis]

do you dive with two computers?

Diving with two computers at the recreational level is insurance against missing subsequent dives within a short time period. If one dies, you still have one that knows your tissue loading. Otherwise, folks will typically sit out 24 hours so a newly rented computer (or table-based plans) and tissues agree.

 

[rhwestfall]

Backup computer? Are you taking about a backup that you keep in your dive bag incase your primary goes down or do you dive with two computers?

Could be either. That is a risk analysis for what you are willing to miss if your computer goes down. Either sit it out for time (24 hours) to reset your tissue loading to use a computer with no dive info, or keep on diving because your back-up has been diving with you and is current on nitrogen loading..... Choices you need to understand and be willing to accept.

 

[SaltyCracker]

Ah yes, I forgot to think about the computers needing to agree for immediate dives.
So then, how important would it be to use the same computer? I get it that they don't have to be the same but wouldn't that be the safest scenario?

 

[Marie13]

Another important plus to Shearwaters. They don’t lock you out.

 

[rhwestfall]

A little story. I did a pair of dives with my main computer on my wrist and a different backup in my pocket. Dives went fine, 130' and no mandatory stops. At the end of the day while putting things away, I realized I locked out my backup during dive 1 and it was only in free dive mode. Had I needed it, I would have been screwed. For me, it is appropriate to have computers doing the same thing...

YMMV.

 

[SaltyCracker]

Another important plus to Shearwaters. They don’t lock you out.

I bought something else.

 

[SaltyCracker]

A little story. I did a pair of dives with my main computer on my wrist and a different backup in my pocket. Dives went fine, 130' and no mandatory stops. At the end of the day while putting things away, I realized I locked out my backup during dive 1 and it was only in free dive mode. Had I needed it, I would have been screwed. For me, it is appropriate to have computers doing the same thing...

YMMV.

That's what I was thinking. Once I decide to add a backup, it'll just seem logical to use the same computer.

 

[Marie13]

I bought something else.

Too bad. Buy once, cry once, the saying goes.