How essential is a dive computer? When I became certified my instructor stated that all you need was a watch and that computer, “between your ears”. I still agree with this sentiment. I will also say that the deeper and more technical your dive, the more essential a dive computer can be.
My computer is nice to have, but I can get along without it. It doesn’t make it on all trips. I don’t really do a lot of deep or challenging dives. My console provides me with the info I need along with my watch and dive tables. My computer is essentially a device I use for pulling accurate data for my dive log.
All that being said, a lot of divers consider theirs to be essential equipment and they wouldn’t dive without it. So what does a dive computer do?
Dive computers provide and record large amounts of information during a dive. The most common information is depth, time of day, bottom time, water temperature, date, maximum depth, ascent warning, log mode, as well as many others. There are generally two types of computers, stand-alone and air-integrated. Both have their strengths.
Stand-alone computers are independent of your other dive gear. It does not monitor the air in your tank. This is the type of computer that I use. Stand-alone computers can be wrist mounted or in a console with your pressure gauge. Stand-alone computers are easy to use with other dive gear configurations and are generally on the lower end of a manufacturer’s model line.
Air-integrated computers connect to your regulator via the high-pressure port. In most cases they replace the standard analog pressure gauge because they are responsible for measuring the amount of air in your tank. This type of computer is more complicated and relies on electronics to monitor the air supply, depth, bottom time, etc. Basically, it’s an all-in-one package, meaning less to carry. If the batteries or something else fails with the unit, your dive is over. This is one reason why I like analog gauges. As a side note, most computers today are nitrox compatible.
A basic bottom timer may be the way to go. They provide depth, dive time, temperature and maximum depth much as your analog gauges would. They are not computers, meaning they don’t track nitrogen or oxygen exposure. Bottom timers are often used by technical divers when using decompression software to cut dive tables.
As noted earlier, I primarily use my computer as a reference for my dive log. The computers log can be reviewed at your leisure or downloaded to a computer for storage or for building your logbook. The log function can be valuable when planning future dives to the same area, You can look up things like your maximum depth, water temperature, bottom times, etc. This information can make dive planning much easier.
When looking to buy a dive computer, shop around and do some research about the features and functions you really need. Technology changes a lot and great deals can be found on last years models. Models are changing quicker than ever. I recommend getting a computer that is proven and has been on the market for awhile.
As always, talk to your local dive shop. Ask them what computers are selling and which ones get returned the most. Speak with divers who regularly use a computer and find out what they would want if they purchased another computer.
Good luck and good diving!