Am I the only one that dives with 2 computers?

[tbone1004]

All these absolute statements. It depends a lot on the diving one is doing. In my case I really do not want to trash the second dive of a two dive trip. First dive is usually 80-100 ft. Usually multilvel. If I turn the dive, then except in a dire emergency I am not going up. I am heading back to the anchor line and do a safe ascent. So I could be down for several more minutes.

I have had a computer flood on me though that was on a reef dive in the Keys so NDL exceeds dive time.

I do have a second computer. It only has to save me a couple dives and it pays for itself. It also saves me a lot of what if concerns.

My backup is a zoop. It does not lock you out if you go into deco unless you are skipping steps coming up.

I can use tables. But I get more diving and more relaxed diving with two computers. On a given dive depending on water and other conditions the profile can vary greatly.

what is your primary Steve?

 

[Tony387]

Always carry two computers on a trip but only dive with one. I've never had a computer fail but if it did it would be no big deal. I'd just end the dive and grab my other computer for the next dive.

I think that's the difference between a "backup" and merely a "spare."

 

[Dirty-Dog]

Two is one and one is none...

My primary is a Nitek Q, with an Aeris Manta as backup (in gauge mode if it's a deco dive). Before I needed a multi-gas computer, I used the Manta as primary and an XR1-NX as backup.

Your thinking is sound in that it's nice to know that if one fails, your dives can continue unchanged. Reverting to tables is an option, certainly, but as with all table diving, will result in seriously shorter bottom times.

 

[Superlyte27]

​Here's an article from DAN's Alert diver:Your Computer Fails: Now what?

Here's a quote:
"If circumstances require that you switch to a "fresh" machine, says Eric Douglas, director of DAN® Education, a diver will need an extended surface interval to allow his body to offgas accumulated nitrogen. "I would follow the flying-after-diving guidelines before considering myself clear enough to start over," he says. Those recommendations call for a minimum 12-hour surface interval for a single no-decompression dive or a minimum 18-hour interval for multiple dives or multiple days of diving."

I'm like to error on the conservative side. One dive - out for 12 hours, 2 dives - out for 18 hours, 3 or more dives - out for 24 hours, deco dives - out for 48 hours.

If a diver gets bent, it not only affects them but every diver on the live-aboard trip.

Ridiculous...
Figure a square profile, pad the surface interval, and run it on tables with the appropriate group. Amazing that this stuff has been forgotten, hilarious even.

Geez, you guys realize we used to dive WITHOUT computers at all right? You're telling me you can't go backward because the computer fails in the middle of a dive instead of starting a dive without one? Wow.

Get your max depth from your buddy, known depth of the sight or from the sonar on the boat, you know how long you went down for, boat captains and mates are tracking this, as well as your dive buddy. Depth and time, that's all you need. Geesh.

 

[RJP]

I've never had a computer fail but if it did it would be no big deal. I'd just end the dive and grab my other computer for the next dive.

How long of an SI would you take between the two dives?

 

[Subcooled]

If your computer fails (e.g. battery dies in cold water) then you also loose the dive profile information stored within. This alone can be a good (albeit expensive) "non-tech" reason two wear two computers.

"If my computer dies, I still want to launch my SMB from sufficient depth in order not to be overrun by a boat"

And finally, if the dive is a near-mandatory-staged-decompression dive, then carrying a backup depth gauge or a backup computer is a healthy thing. The deeper you go the healthier the backup becomes. Do not forget what happened to Jochen Hasenmayer.

Just don't say "my buddy needs dive hours"

 

[RJP]

Another option to spend funds on is to have an optimal BC for diving at home (cold water/drysuit) and an optimal BC for vacation diving (tropical water/thin wetsuit).

That's what I did... I call it a BP/W.

 

[Subcooled]

Dive tables won't work as a backup if you are doing a lot of diving like on a live-aboard.

Some tables do, but those are not the tables PADI uses.

Yes, you guessed right. The residual nitrogen loading after a dive can be classified (A,B,C,...), and this information can be used to subtract a number of minutes from next dives length, Works well and you can do as many dives as you wish, but of course there is a lot of extra padding then. (...) OK, maybe it doesn't work then...

 

[gopbroek]

II run dual Oceanic's both on DSAT. The primary is a VEO which is easy to read from my wrist, the secondary is a Pro Plus that also gives a convenient gauge pressure readout (in addition to a SPG). As a bonus the ProPlus logs my pressure for download into my Dive log. I am a vacation diver and dive an aggressive schedule and have had computers fail, it's convenient to have a 'hot' backup. Could I survive without a computer that has a record of my residual load? Most likely, but why should I.

 

[FinnMom]

On a liveaboard yes, but the extra one is unobtrusively fastened to a D-ding, or zipped in a pocket. Otherwise only for tech dives.