Buying gear and need advice

[divedeepnj]

There are other things you need first like exposure protection (think: wetsuits that 50 different people have peed in), but get a computer too. If you dive near NY, it would be hard to find a diver who doesn't use a computer. Some people are saying use gauges, that's like saying use a typewriter instead of a laptop. Just learn how to use it, and go conservative for a while. I'm in NJ, and it's EXTREMELY rare for someone to use gauges only.

 

[halocline]

If he had a computer he would have known he was running out of air in enough time to get himself to safety without me having to save him.

Huh? What does a computer have to do with keeping track of your air supply? An SPG works just fine for that. Sounds like this guy just didn't pay attention.

 

[TSandM]

As a new diver, you have a lot of things to think about -- buoyancy, navigation, buddy skills -- and I at least found my bandwidth just wasn't enough for all of it. A computer makes your life a little easier, because it keeps track, according to its algorithm, of how long you have been where you are, and how long you can most likely stay there safely. Air integrated computers will even give you a readout of how long your gas is going to last at your current depth and breathing rate, although there is a LOT more to know about gas management than that. (See my husband's thread.)

I would recommend buying a computer if your budget will accomodate one, and I would highly recommend buying a wrist model. I got tired VERY FAST of having to pull my gauges up in front of my face to look at them. Having gauges on your wrist gives you a "dashboard" of information you can consult with a quick glance, just as you do when driving a car.

As far as other gear goes, the argument always rages between the "rent everything you can so you can make a good decision and buy once" people, and the "buy gear, because if you do you'll dive, and accept that you will probably replace a good deal of it" people. Renting's a big barrier between you and local diving, and local diving is what will make you a good diver (unless you're the kind of person who can travel all the time). So read and think and make the best decisions you can, and get out diving . . . And maybe, if you get really hooked on the sport, you'll replace your first purchases. There are worse things.

 

[Stu S.]

We drift dive in Southeast Florida. We do two dives per boat trip. Using NITROX and a computer allows (about) 80% more bottom time than using tables and air.

Who wouldn't want more bottom time? I sold the depth gauge years ago.

 

[driftwood]

Hey everyone new diver from NYC here. I'm about to buy my first set of scuba gear and need some advice. Should I go straight to computers or start with gauges first?? Any manufacturers to stay away from?

First, any computer you buy should be able to handle Nitrox. Even though you are not Nitrox certified make sure your computer will handle enriched gases. Second, if you can afford it go for an air integrated computer. By the time you buy your SPG and computer, you are not that far from being able to afford an air integrated computer. For a new diver the best feature of the air integrated units is that most will give you a "time remaining" estimate based on your air use and depth. This is both comforting AND tells you when you should start thinking about getting to the surface. Third, make sure that you computer has user replaceable batteries. It's a pain to have to ship it off for a cheap battery and O ring. Forth, back lighting the display is very useful. Another neat thing is the ability to download the data to your computer.

Most of the computers out in the market are great products that are safe and function very reliably. Oceanics seems to be more liberal with NDL's than my Suunto. I have used both. Personally, I love my Cobra, it's pretty simple, robust, and has enough features/settings to adapt to where I dive. I only have two complaints, one, its hard to read out of water with the display protector installed, two, the refresh rate is too slow at factory settings. If you buy one from a shop have them set the refresh rate to the fastest possible. You can only do this using the Dive Manager software with the interface cable.

To sum it up, these are the questions I would ask:

1. Does the computer handle Nitrox?
2. How much more is an air integrated computer over a SPG/computer or analog console?
3. Can the batteries be replaced locally or do I have to ship it to the manufacturer?
4. Is the display lighted?
5. Can I download the data?

Hope this helps, don't settle on a computer that doesn't do what you want. If you can't afford your dream computer right now, save until you can.

 

[halocline]

I disagree with the air integrated purchase for new divers. First, if the computer does go down, you're left with no dive info, no air info, and that's very unsettling for a new diver. Second, the "time remaining" bit based on remaining air is totally dependent on depth and to an extent current consumption rate, and as such, should really be taken with a grain of salt. Both depth and consumption rate change all the time, especially with new divers. Gas management is a skill that simply must be learned early on and starts out really quite simple; pay attention to your air pressure and head for the surface with plenty of reserve. As you get more experience, of course you learn how to estimate that better, how to know what you will use on your ascent and safety stop, etc.

I've always felt that AI computers are a bit of a solution to a non-existent problem, but they do offer some convenience and people like that, so there you have it.

 

[driftwood]

I disagree with the air integrated purchase for new divers. First, if the computer does go down, you're left with no dive info, no air info, and that's very unsettling for a new diver. Second, the "time remaining" bit based on remaining air is totally dependent on depth and to an extent current consumption rate, and as such, should really be taken with a grain of salt. Both depth and consumption rate change all the time, especially with new divers. Gas management is a skill that simply must be learned early on and starts out really quite simple; pay attention to your air pressure and head for the surface with plenty of reserve. As you get more experience, of course you learn how to estimate that better, how to know what you will use on your ascent and safety stop, etc.

I've always felt that AI computers are a bit of a solution to a non-existent problem, but they do offer some convenience and people like that, so there you have it.

A computer failure is "very unsettling" not only to new divers and your dive is over. Do you have any idea of how the 'time remaining" value is calculated? If so please explain.

 

[halocline]

A computer failure is "very unsettling" not only to new divers and your dive is over. Do you have any idea of how the 'time remaining" value is calculated? If so please explain.

Actually, a non-ai computer failure for an experienced diver with a SPG and a buddy need not be scary and dangerous. You use your SPG for gas info, your buddy for depth/time, and either thumb the dive or continue, depending on the profile and whatever other factors play into it, like, is this the first dive of the day, was the profile planned, is it early in the dive, etc. I think the wheel can be pretty helpful in this situation; you can approximate your profile and get a reasonable estimate of N2 loading. If I were in this position, and I was anywhere near NDL when the computer went down, I'd do a much longer safety stop regardless.

In terms of the "time remaining" feature, meaning estimated available gas, I don't know exactly how it's calculated, but it must be some combination of gas pressure, depth, and average consumption rate. I suppose, like NDL calculations, the algorithm varies from one computer to the next. Maybe you can help me out here.

 

[MauiScubaSteve]

In terms of the "time remaining" feature, meaning estimated available gas, I don't know exactly how it's calculated, but it must be some combination of gas pressure, depth, and average consumption rate. I suppose, like NDL calculations, the algorithm varies from one computer to the next. Maybe you can help me out here.

I do not see how anything more than how many psi per breath and how many breath per minute is required for remaining breathing time. Then all you would need is show the time to NDL if less than remaining breathing time. Seems pretty complicated to expect the computer to be assuming average consumption while estimating ascent speed and SS times into the remaining breathing time. This might be why people say don't blindly follow...

For what it's worth, many AI's do not respond when in close proximity to an Apollo scooter (none that have dove with me), and it takes up to a minute for signal reception after shutting the scooter down (annoying to say the least). No data displayed, no ascent alarm, no MOD alarm, no NDL alarm??? My least favorite guest is the one with Air 2 and AI; when we're scooter-ing with rays or sharks you better hear your octo free-flowing over the scooter whine and your own exhalations or you might be really low on air when signal is restored.

 

[halocline]

I do not see how anything more than how many psi per breath and how many breath per minute is required for remaining breathing time. Then all you would need is show the time to NDL if less than remaining breathing time.

Other than with physical monitors, (like on the new Galileo Sol) how is the computer supposed to know when you're breathing? It's connected to the HP port.