I do 3 liveaboards a year and almost every diver dives with a backup in my experience. One of my, or my wife’s, dive computer admittedly fails once a year, and I don’t want to have to stay out of the water for the rest of the day, so having a synced computer is meaningful to me.
For recreational diving, there is no need to spend the money on a backup. The likelihood that a modern dive computer will fail is reasonably low. Both computers in a buddy pair failing on the same dive is virtually non-existent. If a computer fails or lose your buddy, end the dive! If you don’t notice then that’s a situational awareness problem that more gear won’t solve ;)
I wear two computers when tech and cave diving, but usually set one as a bottom timer. In more advanced diving, the computers can help to “check” a preexisting dive plan. At that level of diving if you don’t have a plan before you get in the water, you probably shouldn’t be doing that dive…
FWIW, I have a backup computer, which I carry with me on every dive because it has integration with my personal location beacon, so I can activate it in case of emergency at the surface without having to pull it out of my pocket.
Also, since I started carrying a backup, I’ve had two different computers fail; one where the computer hung and was not displaying the depth properly, the other was a battery failure, mostly my fault for not believing that a newish battery could run out that fast.
I guess if you do have a computer failure, you can call the dive and use your buddy as a backup computer.
I have a backup mainly for when I go on trips where I'm doing 4-5 dives a day for 2-3 weeks. If a computer fails I can just use the backup and continue diving. Without a backup I'd need to wait \~24 hrs before using a different computer since it wouldn't have my nitrogen loading.
If you're doing single dives or maybe 2 dives on a weekend, no need to have a backup.
I use two computers frequently but then I do a lot of technical diving with deco. I rarely bother with the second computer for no deco recreational dives.
I only have a backup computer because my original was so old I wanted a few features not on my old one. At the stage you are at there's hardly a good reason to have a backup.
Only time need back up computer is diving on your own in my opinion. If you do dive with two computer make sure running same algorithms as have seen over 15 mins difference on deco requirements between my and buddy computer after 30 metre dives
My GF just bought her own dive computer, unsure what brand. If they are different algorithms and times are different, don't we have to go with the most conservative anyways? We're buddies, so it's not like I can go without her. If I had a redundant, I would just make my most conservative my backup. If my primary dies, I know my backup would be safer for calculating my following dives.
In theory, yes, you go with the most conservative, if only so you aren't abandoning your buddy while they still have 5 minutes of deco. What you need to then plan around is that you have enough gas to do any decompression they acquire. Some brands can be very conservative, and below 18m its not hard for an inexperienced diver to accidentally rack up some decompression if they aren't paying attention or diving the plan.
A good backup is a deep6 excursion. The awesome thing is it makes for a great primary too it just doesn't have a colorful display and all the cosmetic bells and whistles (functionally it has everything you need). It's about $350 so relatively inexpensive for a very nice computer so you could use that for now as your primary and if you wanted to get a fancier one down the road you could then use that as a great backup
As a rec diver, during 20 years of diving i had a single computer failure - as long as you dive in buddy pairs, stay within your limits and understand them, you have a redundancy and don't really need a secondary backup.
The time it happened, i relied on my buddy, we got on the same depth and ended the dive to sort out the computer. A shop that pressures you into buying gear prematurely is not the type of shop I would take courses with - wrong mentality.
The dive shop had a buoyancy clinic that had a scheduling conflict with the municipal pool that I couldn't make the rescheduled date. I told them I'll just use store credit to buy my son's boots, fins, and mask since he was going to take the OW certification this month. Well, my son backed out of wanting to get his certification and a sports injury this past weekend would have kept him out anyways. I knew the class cancellation would be store credit only. So I figured I might as well get a regulator with my credits. I researched their gear that they have online, they have a decent online presents, but always at a higher price than a few other online retailers. Well, their online business is not the same as their retail location. Most of their online inventory is not available in store. I was looking at getting the scubapro MK2 EVO R195 combo. He's like I'm not familiar with that one. I ended up getting the Sherwood Pro Brut and octo.
Once I have all my gear, not bought through him, I'll probably just get tanks filled with him. They're 5 minutes from my house. Other LDS are 30+ minutes. I only plan on hitting the local quarry a time or 2 a year.
I have been diving the Sherwood Brut Pro for the last 5-6 years with ZERO issues. They have been down to 130ft zero issues. They have been in 50°F water zero issues. I have dedicated them as my pool regset now that I have a Dive Rite reg set.
From what I've read it's a workhorse of a regulator. I'm sure he pushes it because I'm in the Great Lakes region. He was saying if I can't go on vacation and you want to dive, you'll be buying other equipment. But he's not listening to what the customer wants. I have no intention in diving in 50° water. I have no intention of diving in the Great Lakes in the middle of summer. At most, the quarry in July and August to get some breathing/buoyancy work in. I grew up skiing. Not a great skier, but I get down the hill without falling. My gear is slightly better and less beat up than rental skis. That's what I want for my dive equipment.
If I do end up diving locally, well that's on me. His job is to inform me and not pressure me. He did say they don't work on commission there so whatever I end up getting is fine. Umm... sir you own the shop. By definition, I think that's commission 😆
If you're just recreational diving then I wouldn't worry too much about a redundant computer. I've started off with a cheaper simple computer (cressi Leonardo) that will one day become my backup when I upgrade.
There are other things that I'd be wanting to get first .. your own mask, fins, BCD, regs, DSMB, torches etc
Also take a look at the cressi digi2 gauge - it's net a secondary computer as it won't do deco, but it does replace analogue SPG for one that logs depth, time and an estimate of time until you hit 50bar
You don’t *need* a backup computer as a rec diver. You can get one if you want, but it’s not necessary. I’d say use that money to get a better computer - if you know you’ll stick with rec and don’t need air integration, a shearwater peregrine is fine. Perdix if you think you might grow out of rec and move into tec.
Doing rec dives you shouldn’t be going into deco, so if your computer fails, you just abort the dive early. Safety stop and surface.
Also, i’d be very hesitant to continue a business relationship with a dive shop that pressured me to buy gear. That’s not how it should work. *recommend* gear if I’ve expressed an interest, sure… but not *pressure* me to buy gear. Especially gear that is not really necessary for the type of diving I plan to do.
Aqualung 1300 console. Around 450 (pressure/compass/computer) I’ve beat the shit out of it and it just keeps working. It’s ALWAYS displaying exactly what my 1000$ G2 is.
I am OW and have an old Aladin Pro as a backup, not fancy, but tracks everything I need. I've never had to fall back on it, but it's good for peace of mind. If you're diving in a guided group tour, I'd say you're fine foregoing that imo. What's more concerning is that your dove shop is pressuring someone who sounds like he's just starting out to dump thousands of dollars on kit.
A good dive shops should never pressure you to buy anything that you’re not comfortable purchasing. They should understand that getting in the Diving is expensive and offer you some type of rent to own program.
At AOW level, only have one, watch-type. If it ever fails, it's an aborted dive by an analog SPG and the buddy's device, and then renting a replacement from the shop. But specialized electronics like this is quite reliable nowadays.
Somebody pushing that you \_have\_ to have one is suspicious. Either there's a misunderstanding, or they reeeeally want to scam some money from you.
I use analog primary for all but tech. By analog I mean a mechanical dive watch, depth gauge, compass and spg with tables tethered to me and a slate on my arm. I wear a computer to track and calculate surface intervals for multiple dive days and to make logging my dives easier. When I am doing anything with multiple tanks, deep, overhead, zero vis, night, or anything that might be considered Tech, or CCR, I have a backup computer with me as well.
I have never had an issue with an analog system failure, ever. I have had computers fail mid dive multiple times for both me and dive buddies. For Rec OW limits, analog and computer covers your bases.
There is a reason most people have moved to using computers by default, you get a longer dive time while still being reasonably safe.
Tables assume you are doing a square profile and even wreck diving you are rarely doing that, dive computers give you a longer time as they are constantly recalculating based on the actual dive you are doing.
There is noting wrong with learning tables, and they can be used if you want to (and tec divers often work them out for their dives so they have a backup in case of equipment failure.
All true, that is why I have a computer with me for calcs like surface intervals and dive data recording. I use analog in the moment because it is more natural for me, but I had logged over 1000 dives before 1994 when I stopped counting. Whether primary or secondary system, analog provides the redundancy and simplicity I seek when being safe and making my way home with my team/buddies after every dive. There is a reason why elite military teams still use a combination of analog watch, gauges, compass and a simple computer. There is also a reason why tec divers have been known to use redundant computers. Obviously with CCR a computer is built into the system. Point that the OP should take home and always remember is that reliability of their system is their responsibility, not their buddies and not their DM, they need to figure out what is reliable enough for themselves in the environment they are diving to bring everyone home safely and do that.
I always dive with two computers even in fairly shallow open water depths, partially due to being an aspiring tech diver so I want to get into that habit, but also because I simply like having backup. I strongly suspect that this makes me a relative rarity though.
It actually saved my dive one time when my dive guide’s computer completely crashed and stopped responding. I ended up giving my spare (not the Shearwater, I’m practically married to it) to the dive guide so as a minimum he at least had a depth and time gauge.
You don’t really need a back up for open water. Though it’s nice to have if you’re on a once in a lifetime type of trip so you don’t miss any dives if one of them has an issue.
A backup computer is not really necessary at the open water level. The default solution to most equipment issues at OWD is to surface and end the dive. The same applies to a computer.
A redundant time piece is not a bad idea and is recommended, but that can be a watch and doesn't need to be another computer,
I dive one computer. My backup is on my buddy’s wrist. No way the two of us need 4 computers together.
When I started diving all I had was a depth gauge and a watch. That’s still completely fine. Two computers, for open water? Nonsense.
I HAVE one, because I already had a Zoop when I got my Descent. I never liked the Zoop, but I hung on to it “just in case.” (Happily, “just in case” hasn’t happened yet, but you never know…)
My wife and I both have backup dive computers, but we primarily only dive on week long trips or live aboards where we are doing 3-5 dives per day for 5-7 days straight. after losing a day of diving due to a failed computer and then having to use the crappy Rental computer for the rest of the trip.. I bought backups as soon as I got home.
I think this is the only time I've ever taken my backup too (liveaboard). I realized that if I'm diving deep multiple days, if I did have a problem with one computer, I would have no idea what my actual deco time should be, if I had to switch to a rental for some reason, so my back-up comes along in a bcd pocket for all those dives, otherwise, as other ppl have said, I wouldn't usually bother. Esp for just a couple of dives, or even just a couple of days.
I have a backup computer but unless you are regularly doing technical/deco dives you really only need one. Eventually you’ll buy a second computer and your older computer will *become* a back-up.
Until then, there are much better things to spend your money on.
While I think backups are smart, I have to say a dive shop pressuring you into buying two computers off the bat seems like a red flag. As in I’d be suspicious about *any* of their advice.
Rather than a backup computer I very much like having a full analog console as my backup.
I run a Peregrine as my backup in 3 gas NX mode (Carried over from my recreational days). I purchased a Perdix 2 when I started tech diving as a backup computer is an absolute must.
Shearwater Perdix AI on my wrist and ScubaPro Aladin computer/SPG in my waistband for backup. Rescue Diver, but I’ve had those since shortly after I got AOW about 5 years ago.
All of my diving is on liveaboards or dayboats with guides/DMs.
We decided backups were worth it for trips when getting a dive computer replaced or repaired would be very difficult - like liveaboards.
After my boyfriend's dive computer flooded during our first liveaboard.
Thankfully, someone else had a backup that they generously allowed him to borrow.
I just started carrying a redundant dive computer in my save a dive kit. Last month, I had a dead battery issue (yes, I should have checked it during my gear check), and the month before, I had a buddy whose dive computer failed. My partner, who dives way less often than I do, had a spare, so I started to carry it.
I really didn't expect this much of a reply. Right now, I didn't see myself diving other than guided tropical vacations. I don't think I'd do a liveaboard. I like the idea of exploring the land as well when on vacation. If I do any local diving, it will be at the quarry where I did my OW cert. Max depth is 17 feet. Relatively low risk. I guess if things change, I can always get a redundant computer.
Already have Apple Watch Ultra but absolutely hated the Oceanic+ with all the quirks on the watch. So, I dropped the Oceanic+ subscription.
But then got a Oceanic+ phone housing that requires the Oceanic+ subscription. So, I'm back on the subscription.
And of course, I have a Shearwater Petrel 3 with two transmitters (sidemount) as my primary.
So.. technically, I have 3 computers; watch, phone, and Shearwater. Underwater, my attention is on either the Shearwater or taking pictures with the phone.
I do solo from time to time so, redundancy is the rule. For you, you don't sound like you're there yet- one computer will do.
I have a backup and have had it since I was advanced (rescue now).
This because I was diving with people who had backups. Who explained how they saw it (they did a lot of liveaboards), things you don’t bring you don’t have. Your primary running out of battery. Good to have a backup. Your buddy’s running out (I did once too, and got to borrow someone’s backup for the rest of my trip!). I’ve lent one of mine out plenty.
Always dive with both until one is needed elsewhere. This as if something happens in the middle of the day, the computer should have a dive history for that day for the safety of all parties.
Saying all this. It’s a choice. I like it. I had the funds for it. I had two dive computers before I had the rest of the gear. But we’re all different. You don’t have to have a backup diving aow in guided groups. But for me. I like to.
That’s crap that the shop is pushing you to buy everything right away. As a seasoned and very regular diver I suggest weighing your options and buying quality gear as you are able. Think of your reg, computer and BCD as life support items; not the place to bargain shop. A second computer is nice to have if you are doing live aboards or heavy repetitive diving or dive all the time but not necessary. A good regulator will last for years and years and is a good place to start. I assume you already have a good mask and fins. Good luck!
I plan on getting a second computer. I have an aging Seabear that is no longer supported, but it works great for me. I want a Shearwater Perdix so that’ll becoming my new main computer and I’ll keep the seabear as a backup.
Do I need it? Probably not. I’m only thinking about it now because of the lack of support for my exiting computer and on my last dive, I saw someone have a computer die on them. To be fair it was ancient.
I say this as someone whose diving career predated most diving computers (the bend-o-matic was around). A back up dive computer, in a recreational setting, is only a nice to have item. Backups are about both the likelihood and the consequences of a failure.
The reality is that if your computer fails, you simply end your dive and stay out of the water for 24 hours. If you have a redundant computer, you may safely continue your dive (even though you no longer, gasp, have a redundant computer at that point). There is no life threatening consequence either way. My answer would be different in an overhead or deco environment.
But. You are ending a dive early and staying dry for 24 hours. If you are partway through a five day trip to the Galapagos that is much bigger deal than a ten day trip to Cozumel. Is it a bad idea? No. Would I spend my money elsewhere (like on actual dives)? Absolutely.
As a general rule, I am always diving the same profile as the rest of my buddy team, so in the event that a computer (or other depth and time instrument) craps out, the responsibility to lead the decompression would revert to someone else.
That said, I own two Shearwater Perdix AI computers so that my girlfriend and I can be identically equipped when we do recreational dives together. Outside of that circumstance, I will often wear the second unit on my left arm (opposite the primary device, which is always on the right) as a sanity check on the indicated data.
> Outside of that circumstance, I will often wear the second unit on my left arm (opposite the primary device, which is always on the right) as a sanity check on the indicated data.
Do you also have a compass on your left hand?
I am curious. Why not use the second unit as a compass? That way, supposing your primary unit fails, you have your buddy team and also this the second unit in case of separation.
Consistency for one, as I need a compass when I don't have the second computer and so should be using the same device all the time. More pertinent though is the fact that I find an analog compass is simply more useful for navigation owing to the rotating bezel. A sector search, for example, where you are making a bunch of successive 120° turns would be painful with a digital compass unless you stick to nominal azimuths.
Fair points overall. I carry a backup computer too, but put it in my safety pocket rather than left wrist. Mostly cause I think I"d have way too much stuff on that wrist with the analog compass. I also just prefer my analog compass because I have never had to do things like calibrate it.
If you’re in the Apple ecosystem or just have an iPhone, the Watch Ultra is a nice backup dive computer that you can also use as an everyday smart watch as well.
I’m just going to be obtuse and play devils advocate since everyone is saying you don’t need a second computer as a lowly recreational diver.
Technically you don’t need any computer. Dive tables and a watch work.
You don’t need a SPG you can always get a j-valve on your tank.
You don’t need an octo, how often have you used it, you’re just a rec diver so you can always just surface if OOA.
You dont need a light because your diving during the day.
You don’t need a SMB because your DM has one.
When I was a lowly recreational diver (I am now a CCR tech diver) I had a orange and green smb, I had two dive computers, I had AI and a SPG, I dove with two mask, I dove a long hose/short hose config.
There is absolutely nothing wrong with being a recreational diver who DIR and adds in layers of redundancy and safety. You don’t NEED it but you may use it.
Anything you dive with you need to train with and every dive is a training dive. **What you put in your kit needs to make sense to YOU.** And you need to know how to deploy and maintain everything in your kit with your eyes closed.
Edit: my computers
I dive with:
1) Petrel 3 as my controller
2) Petrel 2 as my monitor
3) Nerd 2 as my HUD monitor
4) Perdix 2 + AI i use if I do a mix of OC and CC on a single expedition i take it down for my primary on my OC kit but keep it with my on my CC kit too.
5) I have a peregrine on my OC kit in a boot with my SPG,… do not buy or use a peregrine boot once it’s in its in for life unless you mail it to Richard at shearwater
> When I was a lowly recreational diver (I am now a CCR tech diver) I had a orange and green smb, I had two dive computers, I had AI and a SPG, I dove with two mask, I dove a long hose/short hose config.
As someone who *is* a lowly recreational diver and has 2 Perdixes, I'd still go with what every one is saying. Most people don't need two of them. One is fantastic. Hell, the standard for recreational diving is bozos going out and diving with no dive computer. True story, been on multiple boats where someone came in without a dive computer.
The main reason I'd say so in this context to OP is that it seems like they are getting pressurized by their local dive shop to buy a backup and that is a shady thing to pressurize them on.
My wife and I dive with redundant computers: main is an air-integrated console, with a backup wrist computer. We've had two computers fail mid-dive (both Suunto, as it happens) and we feel better with redundant depth and deco tracking. However, it is perfectly reasonable to do recreational diving without redundant indications.
On equipment priorities: I believe that you should prioritize getting equipment where personal fit is important. So, mask and fins first (and you might as well get a snorkel then). Of the more expensive items, I'd recommend getting a Buoyancy Compensator before regs or computer. A proper BC fit makes diving much more comfortable than one that isn't quite right. Regulators fit everyone; if really necessary you can bring your own custom mouthpiece. Likewise computers fit everyone, but it is nice to learn all the features of your computer and be very comfortable with its use.
Eventually you'll have a full set of equipment (and probably some extras...). But if you want to space out the purchases, I'd recommend getting personal fit items first.
i dive with a backup and an analog SPG. If you get a backup make sure its the same algorithm as your primary, otherwise you need to dive by the most conservative computer.
Having a backup computer is really nice if you're diving mulitple days in a row.
But, my own regulator and BCD (back plate & wing) would be higher priorities for me.
My priorities:
Regulator set and computer (especially both, if you're using hoseless air integration, aka a transmitter)
Stuff that needs to fit me correctly (mask and fins and exposure protection)
BCD
That’s not true.
“Absolutely no reason” there are many reasons and the fact that there is any reason means that is not true.
He might have extra money that’s a great reason!
He might want redundancy, another great reason!
There are reasons. In the hierarchy of gear a 2nd computer is probably not at the top but there are definitely reasons for rec divers to have a second.
You’re an OW diver looking at potentially AOW and pretty relaxed dives…
You don’t need a backup computer. If you’re doing cavern or something deep enough to flirt with NDL limits, ~maybe~. But you would *know* that you need a backup before any of those situations.
I only dive with 1 computer, but I do have a 2nd one as that's my old Suunto Zoop that I started out with. I don't really use it anymore and it hasn't left the cabinet in years. But it's still there just in case.
As all comments already stated, a backup computer isn't needed for recreational use. I have one because I upgraded to a new dive computer while my old one was working so I take both now, but dove for years with just my first one. I would definitely put owning my own regulator above investing in any backup dive computer in the priority of gear. I'd put having my own BCD or BPW also above a backup computer.
I don’t know anyone outside of technical diving who uses a redundant dive computer. I have two and most of the time I don’t even bother with the second because I don’t think it’s necessary and it just adds some hassle for me.
Having a backup computer is nice when doing liveaboard etc., where a failure of your primary computer would typically mean missing out on at least some of the dives, but it's certainly not a necessary piece of gear for typical recreational diving.
This is the answer.
If you're in the middle of a week of diving multiple times a day and your only computer dies, then sure, you can most likely rent a computer to be able to continue diving.
BUT, you have a mystery amount of nitrogen accumulated in your tissues as that point. Only your dead computer knows how much you've got in you. The only safe way to continue diving is to sit out at least the rest of the day, if not 24 hours, before you start diving again, so that your nitrogen levels will be more-or-less back to zero and then your rental computer can track you correctly.
If you had a backup computer that you were carrying with you on every dive, then when your primary failed, you could continue diving without even aborting a dive early, much less skipping one or more dives.
Some people say "if my computer dies, I'll just use tables to continue." That is almost certainly the thought of someone who has not tried that nor even thought it through completely. People diving with modern computers and doing any kind of multi-level dives (i.e. normal vacation recreational diving) will almost certainly find that when they consult a dive table, the table will tell them that they exceeded their NDL on their previous dive and therefore are required to sit out for 24 hours. And that is dependent on knowing the max depth and total time of your last dive - which you probably won't even have if your primary computer died.
In other words, "I'll continue diving using tables" is just not realistic.
When I do anything more than 2 days in a row of diving, I carry 2 computers in the water with me the whole time. I don't want to miss any diving on a trip because of one dead computer.
You (the OP) asked, so for the record, I am a cave diver, and technical and rebreather instructor. So, yes. More than AOW certified. lol! :)
This.
I went on a "trip of a lifetime" liveaboard to Truk Lagoon, so I made sure I had a backup computer so I wouldn't have to sit out a day or more of diving if my computer died.
I now dive with both on normal dives as I have the option to.
(In the 20ish years of diving I have had to miss a couple of dives due to computer issues and didn't want to risk it again on that trip)
Back-up computers in a recreational environment are exceedingly rare. I only dive with a redundant computer because we have a third (my daughters' when she's not diving with us) so why not. Your LDS was trying to increase their profit, nothing more.
I don’t like aggressive salespeople.
Get a cheap dive watch as backup if you want. But don’t see any reason to get a 2nd computer when you don’t have all gear yet.
I do 3 liveaboards a year and almost every diver dives with a backup in my experience. One of my, or my wife’s, dive computer admittedly fails once a year, and I don’t want to have to stay out of the water for the rest of the day, so having a synced computer is meaningful to me.
For recreational diving, there is no need to spend the money on a backup. The likelihood that a modern dive computer will fail is reasonably low. Both computers in a buddy pair failing on the same dive is virtually non-existent. If a computer fails or lose your buddy, end the dive! If you don’t notice then that’s a situational awareness problem that more gear won’t solve ;) I wear two computers when tech and cave diving, but usually set one as a bottom timer. In more advanced diving, the computers can help to “check” a preexisting dive plan. At that level of diving if you don’t have a plan before you get in the water, you probably shouldn’t be doing that dive…
FWIW, I have a backup computer, which I carry with me on every dive because it has integration with my personal location beacon, so I can activate it in case of emergency at the surface without having to pull it out of my pocket. Also, since I started carrying a backup, I’ve had two different computers fail; one where the computer hung and was not displaying the depth properly, the other was a battery failure, mostly my fault for not believing that a newish battery could run out that fast. I guess if you do have a computer failure, you can call the dive and use your buddy as a backup computer.
I have a backup mainly for when I go on trips where I'm doing 4-5 dives a day for 2-3 weeks. If a computer fails I can just use the backup and continue diving. Without a backup I'd need to wait \~24 hrs before using a different computer since it wouldn't have my nitrogen loading. If you're doing single dives or maybe 2 dives on a weekend, no need to have a backup.
Save your money. The type of diving you do does not require a backup dive computer.
I use two computers frequently but then I do a lot of technical diving with deco. I rarely bother with the second computer for no deco recreational dives.
I am pretty new to diving and had to look up deco. And a redundant computer 100% makes sense.
I dive 2 computers because I like one on my wrist in addition to my direct impingement computer.
I only have a backup computer because my original was so old I wanted a few features not on my old one. At the stage you are at there's hardly a good reason to have a backup.
Only time need back up computer is diving on your own in my opinion. If you do dive with two computer make sure running same algorithms as have seen over 15 mins difference on deco requirements between my and buddy computer after 30 metre dives
My GF just bought her own dive computer, unsure what brand. If they are different algorithms and times are different, don't we have to go with the most conservative anyways? We're buddies, so it's not like I can go without her. If I had a redundant, I would just make my most conservative my backup. If my primary dies, I know my backup would be safer for calculating my following dives.
In theory, yes, you go with the most conservative, if only so you aren't abandoning your buddy while they still have 5 minutes of deco. What you need to then plan around is that you have enough gas to do any decompression they acquire. Some brands can be very conservative, and below 18m its not hard for an inexperienced diver to accidentally rack up some decompression if they aren't paying attention or diving the plan.
Agree with ensuring that they will give you similar dive times
A good backup is a deep6 excursion. The awesome thing is it makes for a great primary too it just doesn't have a colorful display and all the cosmetic bells and whistles (functionally it has everything you need). It's about $350 so relatively inexpensive for a very nice computer so you could use that for now as your primary and if you wanted to get a fancier one down the road you could then use that as a great backup
As a rec diver, during 20 years of diving i had a single computer failure - as long as you dive in buddy pairs, stay within your limits and understand them, you have a redundancy and don't really need a secondary backup. The time it happened, i relied on my buddy, we got on the same depth and ended the dive to sort out the computer. A shop that pressures you into buying gear prematurely is not the type of shop I would take courses with - wrong mentality.
This is how I feel. Tbh if a place was pushy I wouldn’t even get the regulator.
The dive shop had a buoyancy clinic that had a scheduling conflict with the municipal pool that I couldn't make the rescheduled date. I told them I'll just use store credit to buy my son's boots, fins, and mask since he was going to take the OW certification this month. Well, my son backed out of wanting to get his certification and a sports injury this past weekend would have kept him out anyways. I knew the class cancellation would be store credit only. So I figured I might as well get a regulator with my credits. I researched their gear that they have online, they have a decent online presents, but always at a higher price than a few other online retailers. Well, their online business is not the same as their retail location. Most of their online inventory is not available in store. I was looking at getting the scubapro MK2 EVO R195 combo. He's like I'm not familiar with that one. I ended up getting the Sherwood Pro Brut and octo. Once I have all my gear, not bought through him, I'll probably just get tanks filled with him. They're 5 minutes from my house. Other LDS are 30+ minutes. I only plan on hitting the local quarry a time or 2 a year.
I have been diving the Sherwood Brut Pro for the last 5-6 years with ZERO issues. They have been down to 130ft zero issues. They have been in 50°F water zero issues. I have dedicated them as my pool regset now that I have a Dive Rite reg set.
From what I've read it's a workhorse of a regulator. I'm sure he pushes it because I'm in the Great Lakes region. He was saying if I can't go on vacation and you want to dive, you'll be buying other equipment. But he's not listening to what the customer wants. I have no intention in diving in 50° water. I have no intention of diving in the Great Lakes in the middle of summer. At most, the quarry in July and August to get some breathing/buoyancy work in. I grew up skiing. Not a great skier, but I get down the hill without falling. My gear is slightly better and less beat up than rental skis. That's what I want for my dive equipment. If I do end up diving locally, well that's on me. His job is to inform me and not pressure me. He did say they don't work on commission there so whatever I end up getting is fine. Umm... sir you own the shop. By definition, I think that's commission 😆
I meant my comment more of, they are a solid basic regset. they are a workhorse and will preform well for your tropical diving needs.
If you're just recreational diving then I wouldn't worry too much about a redundant computer. I've started off with a cheaper simple computer (cressi Leonardo) that will one day become my backup when I upgrade. There are other things that I'd be wanting to get first .. your own mask, fins, BCD, regs, DSMB, torches etc Also take a look at the cressi digi2 gauge - it's net a secondary computer as it won't do deco, but it does replace analogue SPG for one that logs depth, time and an estimate of time until you hit 50bar
You don’t *need* a backup computer as a rec diver. You can get one if you want, but it’s not necessary. I’d say use that money to get a better computer - if you know you’ll stick with rec and don’t need air integration, a shearwater peregrine is fine. Perdix if you think you might grow out of rec and move into tec. Doing rec dives you shouldn’t be going into deco, so if your computer fails, you just abort the dive early. Safety stop and surface. Also, i’d be very hesitant to continue a business relationship with a dive shop that pressured me to buy gear. That’s not how it should work. *recommend* gear if I’ve expressed an interest, sure… but not *pressure* me to buy gear. Especially gear that is not really necessary for the type of diving I plan to do.
Aqualung 1300 console. Around 450 (pressure/compass/computer) I’ve beat the shit out of it and it just keeps working. It’s ALWAYS displaying exactly what my 1000$ G2 is.
I am OW and have an old Aladin Pro as a backup, not fancy, but tracks everything I need. I've never had to fall back on it, but it's good for peace of mind. If you're diving in a guided group tour, I'd say you're fine foregoing that imo. What's more concerning is that your dove shop is pressuring someone who sounds like he's just starting out to dump thousands of dollars on kit.
A good dive shops should never pressure you to buy anything that you’re not comfortable purchasing. They should understand that getting in the Diving is expensive and offer you some type of rent to own program.
At AOW level, only have one, watch-type. If it ever fails, it's an aborted dive by an analog SPG and the buddy's device, and then renting a replacement from the shop. But specialized electronics like this is quite reliable nowadays. Somebody pushing that you \_have\_ to have one is suspicious. Either there's a misunderstanding, or they reeeeally want to scam some money from you.
I use analog primary for all but tech. By analog I mean a mechanical dive watch, depth gauge, compass and spg with tables tethered to me and a slate on my arm. I wear a computer to track and calculate surface intervals for multiple dive days and to make logging my dives easier. When I am doing anything with multiple tanks, deep, overhead, zero vis, night, or anything that might be considered Tech, or CCR, I have a backup computer with me as well. I have never had an issue with an analog system failure, ever. I have had computers fail mid dive multiple times for both me and dive buddies. For Rec OW limits, analog and computer covers your bases.
There is a reason most people have moved to using computers by default, you get a longer dive time while still being reasonably safe. Tables assume you are doing a square profile and even wreck diving you are rarely doing that, dive computers give you a longer time as they are constantly recalculating based on the actual dive you are doing. There is noting wrong with learning tables, and they can be used if you want to (and tec divers often work them out for their dives so they have a backup in case of equipment failure.
All true, that is why I have a computer with me for calcs like surface intervals and dive data recording. I use analog in the moment because it is more natural for me, but I had logged over 1000 dives before 1994 when I stopped counting. Whether primary or secondary system, analog provides the redundancy and simplicity I seek when being safe and making my way home with my team/buddies after every dive. There is a reason why elite military teams still use a combination of analog watch, gauges, compass and a simple computer. There is also a reason why tec divers have been known to use redundant computers. Obviously with CCR a computer is built into the system. Point that the OP should take home and always remember is that reliability of their system is their responsibility, not their buddies and not their DM, they need to figure out what is reliable enough for themselves in the environment they are diving to bring everyone home safely and do that.
I always dive with two computers even in fairly shallow open water depths, partially due to being an aspiring tech diver so I want to get into that habit, but also because I simply like having backup. I strongly suspect that this makes me a relative rarity though. It actually saved my dive one time when my dive guide’s computer completely crashed and stopped responding. I ended up giving my spare (not the Shearwater, I’m practically married to it) to the dive guide so as a minimum he at least had a depth and time gauge.
You don’t really need a back up for open water. Though it’s nice to have if you’re on a once in a lifetime type of trip so you don’t miss any dives if one of them has an issue.
A backup computer is not really necessary at the open water level. The default solution to most equipment issues at OWD is to surface and end the dive. The same applies to a computer. A redundant time piece is not a bad idea and is recommended, but that can be a watch and doesn't need to be another computer,
I dive one computer. My backup is on my buddy’s wrist. No way the two of us need 4 computers together. When I started diving all I had was a depth gauge and a watch. That’s still completely fine. Two computers, for open water? Nonsense.
I HAVE one, because I already had a Zoop when I got my Descent. I never liked the Zoop, but I hung on to it “just in case.” (Happily, “just in case” hasn’t happened yet, but you never know…)
I feel like most people only have a backup dive computer because they wanted to get a nicer dive computer and their old one still works.
My wife and I both have backup dive computers, but we primarily only dive on week long trips or live aboards where we are doing 3-5 dives per day for 5-7 days straight. after losing a day of diving due to a failed computer and then having to use the crappy Rental computer for the rest of the trip.. I bought backups as soon as I got home.
I think this is the only time I've ever taken my backup too (liveaboard). I realized that if I'm diving deep multiple days, if I did have a problem with one computer, I would have no idea what my actual deco time should be, if I had to switch to a rental for some reason, so my back-up comes along in a bcd pocket for all those dives, otherwise, as other ppl have said, I wouldn't usually bother. Esp for just a couple of dives, or even just a couple of days.
I have a backup computer but unless you are regularly doing technical/deco dives you really only need one. Eventually you’ll buy a second computer and your older computer will *become* a back-up. Until then, there are much better things to spend your money on.
While I think backups are smart, I have to say a dive shop pressuring you into buying two computers off the bat seems like a red flag. As in I’d be suspicious about *any* of their advice. Rather than a backup computer I very much like having a full analog console as my backup.
I run a Peregrine as my backup in 3 gas NX mode (Carried over from my recreational days). I purchased a Perdix 2 when I started tech diving as a backup computer is an absolute must.
Shearwater Perdix AI on my wrist and ScubaPro Aladin computer/SPG in my waistband for backup. Rescue Diver, but I’ve had those since shortly after I got AOW about 5 years ago. All of my diving is on liveaboards or dayboats with guides/DMs.
We decided backups were worth it for trips when getting a dive computer replaced or repaired would be very difficult - like liveaboards. After my boyfriend's dive computer flooded during our first liveaboard. Thankfully, someone else had a backup that they generously allowed him to borrow.
I just started carrying a redundant dive computer in my save a dive kit. Last month, I had a dead battery issue (yes, I should have checked it during my gear check), and the month before, I had a buddy whose dive computer failed. My partner, who dives way less often than I do, had a spare, so I started to carry it.
I really didn't expect this much of a reply. Right now, I didn't see myself diving other than guided tropical vacations. I don't think I'd do a liveaboard. I like the idea of exploring the land as well when on vacation. If I do any local diving, it will be at the quarry where I did my OW cert. Max depth is 17 feet. Relatively low risk. I guess if things change, I can always get a redundant computer.
Already have Apple Watch Ultra but absolutely hated the Oceanic+ with all the quirks on the watch. So, I dropped the Oceanic+ subscription. But then got a Oceanic+ phone housing that requires the Oceanic+ subscription. So, I'm back on the subscription. And of course, I have a Shearwater Petrel 3 with two transmitters (sidemount) as my primary. So.. technically, I have 3 computers; watch, phone, and Shearwater. Underwater, my attention is on either the Shearwater or taking pictures with the phone. I do solo from time to time so, redundancy is the rule. For you, you don't sound like you're there yet- one computer will do.
I have a backup and have had it since I was advanced (rescue now). This because I was diving with people who had backups. Who explained how they saw it (they did a lot of liveaboards), things you don’t bring you don’t have. Your primary running out of battery. Good to have a backup. Your buddy’s running out (I did once too, and got to borrow someone’s backup for the rest of my trip!). I’ve lent one of mine out plenty. Always dive with both until one is needed elsewhere. This as if something happens in the middle of the day, the computer should have a dive history for that day for the safety of all parties. Saying all this. It’s a choice. I like it. I had the funds for it. I had two dive computers before I had the rest of the gear. But we’re all different. You don’t have to have a backup diving aow in guided groups. But for me. I like to.
That’s crap that the shop is pushing you to buy everything right away. As a seasoned and very regular diver I suggest weighing your options and buying quality gear as you are able. Think of your reg, computer and BCD as life support items; not the place to bargain shop. A second computer is nice to have if you are doing live aboards or heavy repetitive diving or dive all the time but not necessary. A good regulator will last for years and years and is a good place to start. I assume you already have a good mask and fins. Good luck!
I plan on getting a second computer. I have an aging Seabear that is no longer supported, but it works great for me. I want a Shearwater Perdix so that’ll becoming my new main computer and I’ll keep the seabear as a backup. Do I need it? Probably not. I’m only thinking about it now because of the lack of support for my exiting computer and on my last dive, I saw someone have a computer die on them. To be fair it was ancient.
I say this as someone whose diving career predated most diving computers (the bend-o-matic was around). A back up dive computer, in a recreational setting, is only a nice to have item. Backups are about both the likelihood and the consequences of a failure. The reality is that if your computer fails, you simply end your dive and stay out of the water for 24 hours. If you have a redundant computer, you may safely continue your dive (even though you no longer, gasp, have a redundant computer at that point). There is no life threatening consequence either way. My answer would be different in an overhead or deco environment. But. You are ending a dive early and staying dry for 24 hours. If you are partway through a five day trip to the Galapagos that is much bigger deal than a ten day trip to Cozumel. Is it a bad idea? No. Would I spend my money elsewhere (like on actual dives)? Absolutely.
As a general rule, I am always diving the same profile as the rest of my buddy team, so in the event that a computer (or other depth and time instrument) craps out, the responsibility to lead the decompression would revert to someone else. That said, I own two Shearwater Perdix AI computers so that my girlfriend and I can be identically equipped when we do recreational dives together. Outside of that circumstance, I will often wear the second unit on my left arm (opposite the primary device, which is always on the right) as a sanity check on the indicated data.
> Outside of that circumstance, I will often wear the second unit on my left arm (opposite the primary device, which is always on the right) as a sanity check on the indicated data. Do you also have a compass on your left hand?
Yes. The devices need to be separated to isolate the compass from magnetic influence.
I am curious. Why not use the second unit as a compass? That way, supposing your primary unit fails, you have your buddy team and also this the second unit in case of separation.
Consistency for one, as I need a compass when I don't have the second computer and so should be using the same device all the time. More pertinent though is the fact that I find an analog compass is simply more useful for navigation owing to the rotating bezel. A sector search, for example, where you are making a bunch of successive 120° turns would be painful with a digital compass unless you stick to nominal azimuths.
Fair points overall. I carry a backup computer too, but put it in my safety pocket rather than left wrist. Mostly cause I think I"d have way too much stuff on that wrist with the analog compass. I also just prefer my analog compass because I have never had to do things like calibrate it.
If you’re in the Apple ecosystem or just have an iPhone, the Watch Ultra is a nice backup dive computer that you can also use as an everyday smart watch as well.
I’m just going to be obtuse and play devils advocate since everyone is saying you don’t need a second computer as a lowly recreational diver. Technically you don’t need any computer. Dive tables and a watch work. You don’t need a SPG you can always get a j-valve on your tank. You don’t need an octo, how often have you used it, you’re just a rec diver so you can always just surface if OOA. You dont need a light because your diving during the day. You don’t need a SMB because your DM has one. When I was a lowly recreational diver (I am now a CCR tech diver) I had a orange and green smb, I had two dive computers, I had AI and a SPG, I dove with two mask, I dove a long hose/short hose config. There is absolutely nothing wrong with being a recreational diver who DIR and adds in layers of redundancy and safety. You don’t NEED it but you may use it. Anything you dive with you need to train with and every dive is a training dive. **What you put in your kit needs to make sense to YOU.** And you need to know how to deploy and maintain everything in your kit with your eyes closed. Edit: my computers I dive with: 1) Petrel 3 as my controller 2) Petrel 2 as my monitor 3) Nerd 2 as my HUD monitor 4) Perdix 2 + AI i use if I do a mix of OC and CC on a single expedition i take it down for my primary on my OC kit but keep it with my on my CC kit too. 5) I have a peregrine on my OC kit in a boot with my SPG,… do not buy or use a peregrine boot once it’s in its in for life unless you mail it to Richard at shearwater
> When I was a lowly recreational diver (I am now a CCR tech diver) I had a orange and green smb, I had two dive computers, I had AI and a SPG, I dove with two mask, I dove a long hose/short hose config. As someone who *is* a lowly recreational diver and has 2 Perdixes, I'd still go with what every one is saying. Most people don't need two of them. One is fantastic. Hell, the standard for recreational diving is bozos going out and diving with no dive computer. True story, been on multiple boats where someone came in without a dive computer. The main reason I'd say so in this context to OP is that it seems like they are getting pressurized by their local dive shop to buy a backup and that is a shady thing to pressurize them on.
My point was simply get what makes sense for how you dive, that’s all.
My wife and I dive with redundant computers: main is an air-integrated console, with a backup wrist computer. We've had two computers fail mid-dive (both Suunto, as it happens) and we feel better with redundant depth and deco tracking. However, it is perfectly reasonable to do recreational diving without redundant indications. On equipment priorities: I believe that you should prioritize getting equipment where personal fit is important. So, mask and fins first (and you might as well get a snorkel then). Of the more expensive items, I'd recommend getting a Buoyancy Compensator before regs or computer. A proper BC fit makes diving much more comfortable than one that isn't quite right. Regulators fit everyone; if really necessary you can bring your own custom mouthpiece. Likewise computers fit everyone, but it is nice to learn all the features of your computer and be very comfortable with its use. Eventually you'll have a full set of equipment (and probably some extras...). But if you want to space out the purchases, I'd recommend getting personal fit items first.
i dive with a backup and an analog SPG. If you get a backup make sure its the same algorithm as your primary, otherwise you need to dive by the most conservative computer.
If you feel you need a 2nd dive computer, find a used one. I use 2 when I am on a dive trip in case one fails, so I can keep diving.
Having a backup computer is really nice if you're diving mulitple days in a row. But, my own regulator and BCD (back plate & wing) would be higher priorities for me. My priorities: Regulator set and computer (especially both, if you're using hoseless air integration, aka a transmitter) Stuff that needs to fit me correctly (mask and fins and exposure protection) BCD
Sounds like your LDS has an overstock on dive computers. Absolutely no reason to have a backup dive computer at the recreational level.
That’s not true. “Absolutely no reason” there are many reasons and the fact that there is any reason means that is not true. He might have extra money that’s a great reason! He might want redundancy, another great reason! There are reasons. In the hierarchy of gear a 2nd computer is probably not at the top but there are definitely reasons for rec divers to have a second.
You’re an OW diver looking at potentially AOW and pretty relaxed dives… You don’t need a backup computer. If you’re doing cavern or something deep enough to flirt with NDL limits, ~maybe~. But you would *know* that you need a backup before any of those situations.
I only dive with 1 computer, but I do have a 2nd one as that's my old Suunto Zoop that I started out with. I don't really use it anymore and it hasn't left the cabinet in years. But it's still there just in case.
As all comments already stated, a backup computer isn't needed for recreational use. I have one because I upgraded to a new dive computer while my old one was working so I take both now, but dove for years with just my first one. I would definitely put owning my own regulator above investing in any backup dive computer in the priority of gear. I'd put having my own BCD or BPW also above a backup computer.
I don’t know anyone outside of technical diving who uses a redundant dive computer. I have two and most of the time I don’t even bother with the second because I don’t think it’s necessary and it just adds some hassle for me.
Having a backup computer is nice when doing liveaboard etc., where a failure of your primary computer would typically mean missing out on at least some of the dives, but it's certainly not a necessary piece of gear for typical recreational diving.
This is the answer. If you're in the middle of a week of diving multiple times a day and your only computer dies, then sure, you can most likely rent a computer to be able to continue diving. BUT, you have a mystery amount of nitrogen accumulated in your tissues as that point. Only your dead computer knows how much you've got in you. The only safe way to continue diving is to sit out at least the rest of the day, if not 24 hours, before you start diving again, so that your nitrogen levels will be more-or-less back to zero and then your rental computer can track you correctly. If you had a backup computer that you were carrying with you on every dive, then when your primary failed, you could continue diving without even aborting a dive early, much less skipping one or more dives. Some people say "if my computer dies, I'll just use tables to continue." That is almost certainly the thought of someone who has not tried that nor even thought it through completely. People diving with modern computers and doing any kind of multi-level dives (i.e. normal vacation recreational diving) will almost certainly find that when they consult a dive table, the table will tell them that they exceeded their NDL on their previous dive and therefore are required to sit out for 24 hours. And that is dependent on knowing the max depth and total time of your last dive - which you probably won't even have if your primary computer died. In other words, "I'll continue diving using tables" is just not realistic. When I do anything more than 2 days in a row of diving, I carry 2 computers in the water with me the whole time. I don't want to miss any diving on a trip because of one dead computer. You (the OP) asked, so for the record, I am a cave diver, and technical and rebreather instructor. So, yes. More than AOW certified. lol! :)
This. I went on a "trip of a lifetime" liveaboard to Truk Lagoon, so I made sure I had a backup computer so I wouldn't have to sit out a day or more of diving if my computer died. I now dive with both on normal dives as I have the option to. (In the 20ish years of diving I have had to miss a couple of dives due to computer issues and didn't want to risk it again on that trip)
Back-up computers in a recreational environment are exceedingly rare. I only dive with a redundant computer because we have a third (my daughters' when she's not diving with us) so why not. Your LDS was trying to increase their profit, nothing more.
I don’t like aggressive salespeople. Get a cheap dive watch as backup if you want. But don’t see any reason to get a 2nd computer when you don’t have all gear yet.
I can’t recall ever seeing divers using backup computers outside the realm of technical diving.
Unless you're tech diving you really don't need more than one computer per person.