What factor is most important to *you* when you choose a dive computer?

[scubadada]

I know what you get, but why on earth do you want it?

I agree completely: to each their own, to use a gender neutralizing plural in a singular context. People enjoy all sorts of reflective pastimes.

Because, it brings me pleasure and enjoyment. You're an even more crotchety old gomer than I am.

Good diving, Craig

 

[dmaziuk]

I submit that a computer that's too customizable is MORE dangerous in the hands of an average diver than a computer whose algorithm may not conform to the latest and greatest thinking. People could simply try to force it to give them the max bottom time in such a way that jeopardizes their safety.

Only if it lets them push it that far. It's mostly academic, though, because you can't overcome stupid: if they want to get bent, they will no matter what computer and algorithm you give them. And conversely if you understand what you're doing...

 

[scubadada]

Only if it lets them push it that far. It's mostly academic, though, because you can't overcome stupid: if they want to get bent, they will no matter what computer and algorithm you give them. And conversely if you understand what you're doing...

The Hollis TX1 allows a maximum GF of 90, lo and hi, I guess they don't necessarily trust their customers either

 

[dmaziuk]

The Hollis TX1 allows a maximum GF of 90, lo and hi, I guess they don't necessarily trust their customers either

Who knows. Maybe the way software is written setting it to 0 would lead to divide by zero which would make the microprocessor they chose burst in flames. There's all kinds of safety margins you have to set when building mission-critical gear.

 

[Diving Dubai]

Okay, I'll play.

I wanted (needed) a multi gas model. I also wanted a bigger easy to read display. AI was high on my list as I wanted the information to hand rather than fumbling with an SPG on my regular sites that have high current. I wasn't fussed on user changeable batteries, my unit is rechargeable, it has a run time of 30 hrs in my config which is generally enough for a weeks diving without charging, but given if I go away I always take an iPad that will require daily charging and my computer can use that, then that's not an issue.

Not fussed about conservatism, frankly I'd rather be on the safe side than go in a chamber. I didn't want a watch style as the display was too small for me, and my computer is my computer, my watch my watch.

My charging lead happens to be my data download lead. I use it to transfer my dives to my logging software, not too fussed on some of the data, although its good over time to monitor SAC rates especially on dives with high stress loads etc. I can use that info for my Rock bottom calcs, to ensure they err well into the area of caution.

For me I chose the Eon steel, I particularly love the graphical display, where you can glance at a graphic to see where you are on Air or NDL rather than having to read a number (although the numbers are there)

Both my wife and I use Eons, people we buddy with have OSTC, Galileo"s etc and we don't see much discrepancy between them.

 

[Macan]

My top 7 list of features:

1. Algorithm: Buhlmann ZHL16c with user changeable GF and/or fully-disclosed GF settings in Rec mode similar to the Shearwater implementation.

2. Mixed Gas: Capable of (at least) 3 Gas Switch up to 100% O2. Some people think they'll start with a low-end computer then they'll use it as a backup DC when they move on to advanced deep/wreck or Tec. The sad truth is you can't use a basic single gas Nitrox computer like a Zoop as a proper backup for Tec. It will lock-up when you're on an Accelerated Deco sched. Even if you're not planning to do Tec, a multi-gas computer will allow you to extend your recreational Dive Time without ever exceeding NDL by gas switching between 2 EANx mixes using a stage cylinder. I include this in my recreational Deep/Wreck Specialty courses.

3. Battery: User replaceable. I use a Suunto D9, the battery was just changed in Jan. Now, it's on low batt again. It'll have to go to the shop for a week and cost $$ to change the Batt . To be fair, I have well over 100 dives on the D9 in just the past 6 months with around 30% on deep deco dives. In contrast, my primary DC is a Petrel 2. When the low batt warning comes out, just slide in a new AA battery and you're good to go.

4. Software/Firmware Update: User updatable via Internet. This is an essential feature to protect your investment (and yourself). Many computers out there require you to send your computer back to the shop or worse, not updatable at all.

5. Wireless Air Integration: Built in. On doubles, I use a Suunto D9 transmitter on my right post. Conventional SPG on the left. The ability to simply flick your wrist to check gas remaining is very very nice especially when you have two deco bottles slung on the left and/or in a tight situation. Air Integration is like Keyless Entry or Parking Sensors. You can read about them, rationalize them, dislike them, but until you actually put them through the paces, you won't be able to experience their true value. And when you do, you'll wonder how you managed without these features.

6. Display: Color OLED or LED LCD. There's no looking back after this .

7. Wireless Smartphone/PC Interface: Bluetooth. After a dive, I just activate the Data Upload feature on the Petrel 2 and my complete dive profile is uploaded to my iPhone Dive Log app in just a few seconds. No wires or any H/W attachment needed. No more excuses not to log your dives . No need to bring a laptop on multiday dive trips to log your dive or review your profile. Wireless data transmission is also available on the H3 BUT on NFC instead of Bluetooth. It'll work on Androids but not on Apple devices . Shearwater got it right by using Bluetooth instead of NFC.

Unfortunately, there is no Dive Computer in the market today that fits this list. The closest that I can think of is the Shearwater Petrel or Perdix and perhaps the OSTC. They have everything listed except wireless Air Integration .

If i could add one last item, it'll be customer service. It's not a product feature. It's a promise to the customer.

Just my 2 bar thoughts.

 

[RonR]

My top 7 list of features:

...
3. Battery: User replaceable. I use a Suunto D9, the battery was just changed in Jan. Now, it's on low batt again. It'll have to go to the shop for a week and cost $$ to change the Batt . To be fair, I have well over 100 dives on the D9 in just the past 6 months with around 30% on deep deco dives. In contrast, my primary DC is a Petrel 2. When the low batt warning comes out, just slide in a new AA battery and you're good to go.
....

A thoughtful post, and appreciated. What would your feelings be re. a long lasting (40-60 diving hours, say) rechargeable battery, that could be charged without opening anything, and could be user replaced if it was ever necessary?

re. the original question, feature lists don't capture everything- in particular user interface details or customer service. I've run across feature rich computers that were so difficult to use they might as well have been basic models, or doorstops. If you are a recreational diver who doesn't dive all the time, I'd put an easily comprehensible interface near the top of the list.

-Ron

 

[Macan]

Thanks Ron. If the trade-off of a rechargeable battery is a smaller wrist watch form factor, that would be very very nice . If the rechargeable battery is also user replaceable if needed, that would be a winner! I belong to the camp that wants a DC that's wrist watch style and will accept a long lasting rechargeable battery.

You are correct that the User Interface is a critical element. I use a Suunto D9 (4 buttons) and a Petrel 2 (2 buttons). A simple task such as defining gas mixes and selecting gas is a chore on the Suunto and a breeze on the Petrel.

 

[dmaziuk]

A thoughtful post, and appreciated. What would your feelings be re. a long lasting (40-60 diving hours, say) rechargeable battery, that could be charged without opening anything, and could be user replaced if it was ever necessary?

re. the original question, feature lists don't capture everything- in particular user interface details or customer service. I've run across feature rich computers that were so difficult to use they might as well have been basic models, or doorstops. If you are a recreational diver who doesn't dive all the time, I'd put an easily comprehensible interface near the top of the list.

I wonder how much battery life you'd get out of a eInk/ePaper display. That should work great for sunny reef diving and at night you can just shine your light at it. You could probably offer the same unit with eInk or OLED/TFT screens with a little design cleverness.

Anyway, IMO the big deal about recharge vs replace is that the former takes hours while the latter takes minutes.

The interface is difficult. I don't do nitrox and I often forget to set my Leonardo to local timezone when I get there, its interface is just fine with me. I can easily see someone who dives different mixes all the time hating it: changing O2% with one button for every dive and tiny O2 loading bar would be a pain.

 

[The Chairman]

Pete,

Whenever you dive SM in the future, would you mind taking a pic and sending it to me? I'd like to see how you have it set up, as I have an Aeris A300 CS with 2 transmitters, and I was thinking of putting that on my SM configuration.

Sure... I think I have the left tank set up outside already, so when the sun comes out AND the rain stops, I'll post that up here. BTW, @wetb4igetinthewater if you want to get my, or anyone's, attention, use @username like I did with you.

IMO the big deal about recharge vs replace is that the former takes hours while the latter takes minutes.

I use rechargeable batteries in both of my Petrel 2s. I simply have two batteries for each unit and they use the same charger as my 18650s that I use in my lights. One charges while I dive the other. Pretty easy and I don't feel compelled to completely drain a battery before I change it. 2/3s drained and I pop a charged one in.

Why do some people want to download data from past dives on their home computer?

Back when I got my first AI PDC, the Cobra, I learned a lot from doing just that. It became readily apparent that my safety stops were only safety pauses and that I ascended way too quickly. It was an eye opener for me as the truth often is.