Analog Gauges or Computer

[ScubaDadMiami]

I would stay away from dive "computers" (which calculate your profile for you and cost way more) and instead get digital gauges (accurate gauges that don't calculate your profile) for depth and bottom time. Become proficient with your diving skills instead of relying on computers.

Many use depth/bottom timer units like the Uwatec, which is also sold under various brand names like OMS and Scubapro. These run for about $150 or less.

On the other hand, there are digitals that you can upload to a computer that are a step up from basic digital gauges for about $125 more. They are also great. You may want to check out something like the Suunto D3.

You can go with analog for pressure. You don't need it to be so accurate that a few psi in one direction or the other matters.

You can even buy a digital compass if you want to spend the bucks. You can got a good old fashioned one for $50 or less.

 

[scubatoys]

I would stay away from dive "computers" (which calculate your profile for you and cost way more) and instead get digital gauges (accurate gauges that don't calculate your profile) for depth and bottom time. Become proficient with your diving skills instead of relying on computers.

Many use depth/bottom timer units like the Uwatec, which is also sold under various brand names like OMS and Scubapro. These run for about $150 or less.

For about $20 more you can get a full functioning dive computer which will calculate bottom time, remaining time, surface intervals, record max depth, etc. Let me think... for $20 do I want to plan all my dives with charts and tables, hope I don't make any math calculation errors, and have to assume square profiles, when in fact I'm diving multilevel so I lose 1/3 to 1/2 my bottom time... to save 20 bucks??


I know there are two distinct camps on this subject. The "don't trust computers" crowd, and the "computers rule" crowd. Every day I drive, I trust the computer in my car to not deploy an airbag into my face at 70mpg, I trust the computer to do my taxes, pay my house note, run my business, heck even keep me alive if I go in for surgery... I think I can trust one to tell me how deep I am, and how long I can stay.

And after handing out dive table tests to 1000's of students from newbie OW students to Instructor cross over candidates.... I'd say without question, there have been more wrong answers on those tests by humans than there have ever been wrong answers displayed on a dive computer.

 

[ScubaDadMiami]

For about $20 more you can get a full functioning dive computer which will calculate bottom time, remaining time, surface intervals, record max depth, etc. Let me think... for $20 do I want to plan all my dives with charts and tables, hope I don't make any math calculation errors, and have to assume square profiles, when in fact I'm diving multilevel so I lose 1/3 to 1/2 my bottom time... to save 20 bucks??


I know there are two distinct camps on this subject. The "don't trust computers" crowd, and the "computers rule" crowd. Every day I drive, I trust the computer in my car to not deploy an airbag into my face at 70mpg, I trust the computer to do my taxes, pay my house note, run my business, heck even keep me alive if I go in for surgery... I think I can trust one to tell me how deep I am, and how long I can stay.

And after handing out dive table tests to 1000's of students from newbie OW students to Instructor cross over candidates.... I'd say without question, there have been more wrong answers on those tests by humans than there have ever been wrong answers displayed on a dive computer.

It's not a question of the computer's accuracy when it works, it's more a question of what does one do that hasn't used a table in years and can't remember how when a computer fails at depth. It's even more fun when one has an "all in one computer" that fails, leaving the diver with virtually no information other than trying to guesstimate how much breathing has he or she has, the depth, the the time and what to do from there. This doesn't matter much on a 30 foot reef dive, but it matters a whole lot more on a 200+ multistop deco profile where a couple of mixes are involved.

Think that's a little far-fetched? You, yourself, mention instructors that make errors in the calculations during cross over exams. The more you do it, the better you get at it. Starting off from day one by becoming dependent on a computer will virtually assure the addiction.

 

[Meng_Tze]

Agree,
If all fails..........you have only your brain left to do calculations......... these can then only be done be based on 'table data'. I am not saying to steer away from computers. They make life so much easier, but as mentioned before, they will fail. Electronics are prone to failure, more over in wet conditions.

By all means use a computer, but also have redundant 'analogue' data available. Combined with resident knowledge of tables, you can always continue/bail out safely.

I think the actual thing here is not 'pro or contra computers', but more 'putting your eggs in one basket or not'.

my $0,02

 

[scubatoys]

Virtually every dive I do, due to the multi level nature, I would be well beyond dive table profiles by half way into the dive... so if the computer has a total melt down, you either use your backup (if you have one) or ascend to 20 feet or so (use your buddies depth gauge/computer to gauge if you are not experienced enough to be able to judge - and there is not safety stop line) then spend about 5 or more minutes there, then exit. Spend the rest of the day either sitting out, or doing dives that are less than 30 feet.

That would be the procedure... but I've yet to have to do it as I have not had a computer give out during a dive... in over 4000 computer dives.

Now mind you... I like dive table problems. I wrote the Computerized Table Tutor which will give you random questions... millions of them. First dive, surface interval, repetitive, missing surface interval, etc. 9 table formats, metric or imperial. So I should tell you, yes, get good at tables, and buy my software to keep practicing... But for scubaboard members, I give it away free if anyone wants it... and when I personally am diving, I do not have a table with me.

 

[Chad Carney]

Steve Miller asked for advice about his first set of gauges... and I have to agree with Larry's advice. (And his prices on computers!)

Once you've stepped over the line, accepting multi level credit on a dive trip, you really can't calculate tables positions anymore anyway. What divers do in the unlikely event of a computer failure, in the real recreational dive world, is get another computer and start diving conservatively on their buddies coat tails. By the second dive day their computers will be close enough to continue moderately safe rec. diving without a hitch. Of course an inexpensive back up hockey puck could have solved the entire issue from minute one. (Yeah I'm only paying my SDI dues now, and they require a computer for OW students.)

I've had a few computer failures over the years since the debut of the Edge, (first one that actually worked), but almost never on my tried and true primary computer. The failure of most new gear occurs during early test dives.

So to me analog depth & time gauges and tables are about like using the front of your t-shirt to try and carry what fell out of your broken basket. (How about a sundial, a lead line and a slide rule?) Keep another reliable basket around, it doesn't cost very much.

Tech diving is obviously a completely different story, but I dive multiple computers along with my laptop programs even then.

Chad, (Confessed gearhead.)

 

[Humuhumunukunukuapua'a]

It's not a question of the computer's accuracy when it works, it's more a question of what does one do that hasn't used a table in years and can't remember how when a computer fails at depth.

Uh...ascend?

 

[Kestrell]

Guages add little to the overall cost of the gear. Some Cressi mini guages will only be $100 to $150 depending on where you get them. I say get the computer and the guages. I have gauges and an Aeris Elite. Great set up for me.

 

[ranger979]

Larry,

I've downloaded the trial version of your software. How do I get the full version free?

Tim

 

[jakubson]

Steve Miller asked for advice about his first set of gauges... and I have to agree with Larry's advice. (And his prices on computers!)

Once you've stepped over the line, accepting multi level credit on a dive trip, you really can't calculate tables positions anymore anyway. What divers do in the unlikely event of a computer failure, in the real recreational dive world, is get another computer and start diving conservatively on their buddies coat tails. By the second dive day their computers will be close enough to continue moderately safe rec. diving without a hitch. Of course an inexpensive back up hockey puck could have solved the entire issue from minute one. (Yeah I'm only paying my SDI dues now, and they require a computer for OW students.)

I've had a few computer failures over the years since the debut of the Edge, (first one that actually worked), but almost never on my tried and true primary computer. The failure of most new gear occurs during early test dives.

So to me analog depth & time gauges and tables are about like using the front of your t-shirt to try and carry what fell out of your broken basket. (How about a sundial, a lead line and a slide rule?) Keep another reliable basket around, it doesn't cost very much.

Tech diving is obviously a completely different story, but I dive multiple computers along with my laptop programs even then.

Chad, (Confessed gearhead.)

I would have to agree with the redundant computer philosophy, especially for a week long dive vacation. A basic Nitrox/Air module that can be carried in a BC pocket is about $225 (right Larry?), air only even less. If you dive 3 dives per day (unlike liveaboards, which is 5 dives per day) for 5 days, the cost of the redundant computer is $15 per dive. Compare this to airfare, hotel, food, ... Of course, you really amortize this cost over many years, since even if you upgrade your "main" computer (new toys are great!) you have no reason to upgrade the spare one.

A hint to keep you from going crazy when diving Nitrox. I dive on liveaboards where the mix is usually between 31% and 32.5%. Unless you are doing longer, deeper profiles, O2 sAT is never an issue. Therefore, I set the backup computer to EAN 30. This provides a conservative backup for nitrogen saturation. I don't change it during the week, so it is not a pain in the a** having two computers. Since I have my main computer on my wrist, and the backup in a console, I can see both and be sure I am not "pushing the tables...oops, I mean the computer."