Ratio is a small Italian company that manufactures a range of incredible dive computers with some very unique features for recreational and technical divers. Being a smaller manufacturer they are able to adapt and experiment much more easily and quickly compared to the main brands who have to go through lengthy R&D and sign off procedures so they are able to bring new technologies to the market much more quickly.
Currently their range only has two main models but each of those is split into varying levels of complexity from purely recreational all the way to rebreather support. There is the watch style iDive which covers everything from free diving to rebreathera and the larger iX3M wrist mounted computer which is more technical focused but the entry level Deep version still provides everything a recreational nitrox diver would need. They share a lot of features but the obvious differences are the size and the screen.
We'll come back to the hardware elements like the screen a little later but first we'll take a look at some of the features that are built into both computers.
Double Core Algorithm
Ratio fit a double core algorithm into the technical level iDive computers and all the iX3M computers that allow complete Buhlmann ZHL-16 B & VPM-B algorithms to be run in real time against your dive data. This method provides incredibly reliable and safe decompression profiles. It also allows the conservatism of the algorithm to be modified on the fly DURING the dive should you dive plan need to change unexpectedly.
The diver has control of the stop range settings, allowing you to modify safety, deep and deco stops depending on your training agency or synchronise with your dive buddy.
USB Rechargeable Battery
Both the iDive and the iX3M feature a rechargeable Li-ion battery that can be connected to any USB source for recharging. With so many USB charging devices these days doesn't it make sense for your dive computer to do the same. It even allows you to take a USB battery pack away with you if you are going to be away from a charging point for a long time.
The iX3M provides up to 40 hours of run time whilst the smaller iDive has 25 minutes but because it is designed as a watch as well it will use less power in time mode and will even go to sleep when no movement has been detected for five minutes to conserve power.
3D Self-Compensating Digital Compass
Both screens are well suited for a digital compass which offers a clear way of navigating underwater with numerical and visual guides. Both are tilt compensating so there is no need to be perfectly level and are accurate to +/- 1 degree.
Ratio have a number of 'apps' that can be installed onto the dive computers to add extra on screen information that could be useful. Some examples of apps are a magnetometer, luxmeter (iX3M), weather forecast, temperature or pedometer (iDive). Granted not everyone is going to find them all useful but the point is that the operating system can be customised and no doubt there will be other apps to try out in the future.
PC / Mac Interface
The charging point is also the interface to connect your dive computer to a PC or Mac, allowing dive profile data to be transferred to their DiveLogger software for analysis and recording. It also allows owners to upload and install the latest firmware versions, eliminating the need to return the computer to a dealer. The interface cable (charging cable) is supplied and DiveLogger software is FREE.
One of the optional accessories available from Ratio is their Oxygen Analyser which actually interfaces with the iX3M and iDive and provides on screen gas analysis. Vandagraph R-22VAN or Analytical Industries PSR-11-39-MD sensors fit the analyser so you are not locked into some obscure fitting sensor.
So let's take a close look at the iDive which comes in five variants (use our Comparison page to view all the features and specifications across the model range):
- iDive Free - Primarily free diving but also supports air scuba diving
- iDive Easy - Nitrox diving with two gas mixes
- iDive Deep - Entry level tech model with three gases and normoxic trimix support
- iDive Tech - Eight gas mixes and some algorithm options
- iDive Reb - Add rebreather support with five gas mixes and three diluents
The iDive is a small watch size computer but it is built to last with a stainless steel housing and scratch resistant sapphire glass that give the iDive a 220m depth rating. The screen maybe small compared to it's bigger brother but it's 80 x 80 pixel full dot matrix configuration allows information to be shown clearly and in an easy to understand format including graphical dive profiles and the digital compass.
Four buttons provide easy navigation through the menu and settings system and gives a familiar look and feel for divers that are used to other well known dive computer brands.
The iDive is definitely targeted more towards divers that want their computer to look as good out of the water as it does in it. Ratio make the iDive in a variety of finishes beyond the standard stainless steel including coated versions or the Jewel versions which are set with Swarovski Elements for a bling level not seen before in a dive computer
The iX3M is the more serious end of the spectrum with all three of the model versions focusing on the technical side of diving (view the feature and specification differences on our Comparison page):
- iX3M Deep - Entry level model with support for up to three normoxic Trimix gases
- iX3M Tech+ - Up to ten gas mixes and greater configuration of the algorithms
- iX3M Reb - Rebreather support with ten mixes and three diluents.
The iX3M features a 2.8" full colour TFT screen with fully customisable colour scheme for impressively clear and bright dive information. The large colour screen allows a far greater amount of information to be displayed in more ways. It also has an impressive viewing angle of over 150 degrees. The housing is depth rated to 300m and packs in some additional hardware over and above the iDive.
Ever wished you had a convenient way of recording your exact location well the iX3M has built in GPS can provides position recording and navigation. It obviously only works on the surface because signal is lost through water but it is still handy as a marker. How about setting the computer to vibrate rather than audible alerts. In fact the iX3M has visual, audible and vibration that can be switched on and off as you like.
There just isn't enough room to list and talk about all the features of the iX3M. To summarise, it does a lot, especially comparing it to competing bigger brand models. If you are after a technical dive computer you should definitely be seriously considering this one.