IT PAINS ME TO ADMIT that I was once prejudiced against computer-watches for everyday timekeeping. I was one of those dinosaurs who believed that a proper watch had hands and a little gold crown in the “12” position.
Over the years, I’ve been worn down. Now I tell the time by the 24-hour clock (which confuses the hell out of American airport check-in staff) and happily wear a digital computer-watch day-to-day. Some smashingly good-looking examples are becoming available, too.
One such was the US-made Oceanic OC1.
It was the first Oceanic computer that I could contemplate using for managing my decompression dives, too.
This was because it came with the option of the Pelagic Z+ algorithm based on the trusted Buhlmann ZHL-16C data, as well as the Pelagic Desat algorithm, designed for repetitive diving within no-stop parameters, and never deeper than 30m. The latter was no good for me!
Now all Oceanic computers are supplied with this option, and it needs only the salesman in the dive store to understand what he is selling.
Are we asking too much Too often I witness people using their Oceanic computers straight out of the box in Pelagic Desat mode for quite adventurous dive profiles. I don’t recommend doing that.
The Oceanic OCS looks superficially like the OC1, but it has no radio link to the pressure of gas in your tank. It can be switched between three different nitrox mixes during a dive.
It’s finished in black composite with stainless-steel trim. As a watch it looks stylish, only quite big, but then that’s fashionable, evidently. My wife currently eschews the dainty gold Rolex her dad bought her in favour of a massive Poseidon diving watch, admired by one and all.

Believe it or not, I have been accused by some of never reading the instruction manuals that come with equipment I get for test.
This may be so with some items, but never with computers. However, there is a tendency for computer manufacturers to supply their manuals in CD form, which is no use to me when I’m thousands of miles from home in a boat, or on an Internet connection on some god-forsaken island, and have blanked out on how to set something.
While on a boat in mid-Pacific, a lady asked me to change her OC1 from the Desat algorithm to the Pelagic Z+.
We were about to do a 60m dive on the wreck of the San Francisco Maru, and she was concerned that until then her OC1 had been out of step with her European-made computer. Which was she to believe
The Oceanic settings menus are so intuitive that I was able to pick the computer up and do it for her. It didn’t help that the algorithm setting is described in the menu as the “NDL Basis” rather than “Algorithm”, but that had already fooled me on an earlier occasion, so I was prepared. The OCS now offers “Algorithm” instead.
It’s all done by a long push on the Mode button, followed by using the three other clearly marked buttons to navigate around and select.
Menu Set A is for setting the alarms. Menu Set U is for things that you are unlikely to change often, such as the units, wet activation, algorithm, conservatism, sampling rate and, unusually, the “deep stop” function (I say unusually because I tend to change this according to the dive I am doing).
Menu Set F is for the nitrox fractions (percentages). You can set up to three mixes for one dive.
It’s nice that you can step backwards through the settings, which eases a lot of the frustration if you inadvertently hit the wrong button.

In The Water
If you read my recent review of the Oceanic Veo 3.0, you already know virtually all you need to know about the OCS computer-watch, because it appears to me to be simply a watch-sized version of that hockey-puck-sized computer.
I particularly liked the way in which, as the no-stop time dwindled to a few minutes, it sounded a warning and flashed a red light at me. There was no mistaking that! All audible alarms can be deactivated once you’ve heard them.
All these new computer-watches are said to be intuitive to set up and use. However, the fact that each one is different tends to send intuition out of the window.
I surprised myself by how easily I could check the alternative displays and swap from one mix to another (to correspond with what I was breathing) during a dive.
The ascent-rate monitor varies the maximum speed allowed (21 to 11m/min) according to your depth at that time.
Once you get up to safety-stop depth, “Safety Stop” is displayed. There is however no countdown until you activate the on-board timer, which appears and counts in minutes and seconds. This feature can be used intelligently for any timing purpose, including the optional deep stops, but you have to press the button appropriately. It also allows you to determine the duration of your safety-stop.
The OCS can also be used in Gauge mode, when the run-timer proves very useful, or in Freediving mode, in which it uses a more frequent sampling rate.
The adjustable brightness backlight makes everything very readable.

The Compass
As on other computer-watches, you call up the Calibrate mode and rotate through 360° to calibrate it. It can be adjusted for declination too. However, I didn’t like the display, which leaves you with an arrow that points to North (for example, depending on the mode selected) and a degree reading of the course indicated.
It does provide a reverse heading feature, but I found it hard to get my head around this.
Luckily, I rarely find myself in such poor visibility that I need to navigate “on instruments”, but you might be different.

The Future
The OCS is firmware update ready. The optional PC interface kit allows you to install operational improvements or even future new features.
Register your purchase for a lifetime warranty that includes a free activation code for an online dive computer-training course, and free replacement batteries every year.

Mares Matrix, £415
Scubapro Meridian, £399
Suunto D4i, £395

PRICE £445
ALGORITHM Choice of two
NITROX 21-100% x 3
PO2 SETTING 1.2-1.6bar
DEEP STOP Optional
ASCENT RATE ALARM 11-21m/min, according to depth
BATTERY CR2450, diver-replaceable but not recommended
DIVER GUIDE width=100% width=100% width=100% width=100% width=100% width=100% width=100% width=100% width=100% width=100%