I'm going to help you determine and decide which computer do I buy within the multiple options that exists. You'll need to consider several factors before choosing your computer. And if you have any doubts, ask me, don't be shy.
Set priorities
Underwater safety is paramount and the most important in this sport. That is why carrying one dive computer per person, apart from being mandatory, is the most recommended. You should not share a computer with your dive buddy, as the dive profiles will never be the same, and also, in case of loss of a buddy, how could you know your ascent speed, your safety stop or your decompressive stops?. At this point, do not skimp, acquire a computer as part of your essential equipment, even before the acquisition of a regulator. But what computer to buy?
And once you've taken care of the importance of your own computer, we get into it... to buy a dive computer you must answer several questions: Which one would I use to start with? Will I know how to handle it? How often should I charge the battery? How does it benefit me to changes the gas? ….endless questions and variables in which I going to explain so you have more options when choosing yours.
Issues to consider
If you're starting out in this sport, you're likely to consider buying a dive computer, but don't want to jump into one of the most expensive or more complex, as you're still not sure how far you're going into this lovely water adventure.
My recommendation is that you acquire a basic one, but perhaps, with some features that allow you to advance in the future and do not limit you in your dives and progressions.
Mixtures
All dive computers, today, show us the essentials at a single glance of the screen (depth, dive time, temperature, ascent speed and safety and deco stops). But not all of them can be given the mixture of the gas you breathe, that is why my recommendation is that you can at least indicate if you are going in Air or Nitrox and their percentage. At first, you may not consider the gas mixture something important or that you are going to use it, but you will be wrong, the Nitrox mixture makes your diving much safer, you have more bottom time and you can make more dives throughout the day of your vacation. And the usual thing in diving trips, is to carry a Nitrox mixture so as not to have as much nitrogen load accumulated in your body. Sooner or later, you will be trained in this essential course to be able to breathe this type of mixture, and you will notice their benefits. So, when buying your computer, do not hesitate to choose one that you can tell which gas mixture you are having.
I recommend training the Nitrox course in https://www.pssworldwide.org/
Batteries
As for the batteries and their durability. It is usual that on most computers, there is the possibility of battery change by the user, it is very simple to change, but you have to take into account several things. User interchangeable batteries, according to manufacturers, usually last between 2-3 years, but the reality is somewhat different. This may become true, if your computer can be turned off completely after use. If on the contrary it stays in clock mode, it will last something less.
If you can change the battery, it's a good option, but as I was saying you should have consider some guidelines:
1) If you make the battery change and your computer is within a 2-year warranty, you will lose that warranty for tampering with it. However, if you take it to an official site, you will have the guarantee of the technical service that has done it for you.
2) It may be easy to change, but you won't be entirely sure you've done it right, until you submerge it, as you won't have a sealing chamber, and you risk having a computer flood in your next dive. In a technical service, even if you're charged for that change, you're making sure you've gone through a sealing test, and that in diving, it's underwater safety.
3) Sometimes in some computers, if we don´t change the battery correctly, their parameters could be deconfigured and some of the information of your dives or software lost. But if you change it in the technical service they will check that everything is perfect.
Everything said, it's great that you can change the batteries, but to me, it´s an option when I´m on a trip. I always take a spare battery, just in case, before starting the diving season I have previously taken my computer to technical service to make the battery change.
And of course, another option, is to buy a dive computer with battery charge via usb cable, or with other kinds of charges. The only thing to keep in mind on this type of computer, is to keep an eye on the percentage of your computer's load before each dive and if necessary put it to load, just like your mobile.
For example, Suunto D5 might be an interesting option, it´s versatility in terms of the recreational and technical functionalities, it comes with a USB charge and the litium battery.
Sizes
This feature is quite subjective and goes a little into the most aesthetic part. The larger ones have a wider display, so underwater we can see the informations bigger. And those that are clock type, allow us to wear them throughout the day, allowing us to know at all times our parameters of surface desaturation. Here, as I explained, it is more of an aesthetic theme than anything else, since the big screens, you usually take them off once you have finished diving.
Extra features
All brands have computers of a basic range and of course, top range. If you are already at the point of making more technical dives, or you are a professional diver, or you do many dives a year, my recommendation is to go to a high range in computers, as the performance increase considerably. You will be able to make several gas changes underwater, go in CCR closed circuit, Trimix mixtures, etc ... set more technical diving parameters, set "Deep Stop" stops, some include digital compasses, even various algorithms that you can determine which one you want to have in each dive planning. Other extra options, some work with GPS, wireless, and / or the ability to connect a gas transmitter.
I hope I have answered several of the questions you may have been asking and I wish you buy a diving computer that fits all your preferences and meets your expectations.
You can check out other issues https://mundobuceo.es/
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