Tissot Sea-Touch: A Review

Separate Or Combo: Choices…Choices…

The dive watch market is a fickle beast; one moment it’s completely fanatical about massive digital displays and chunky boots, the next it’s idolizing the inconspicuous, sleek watches that would pass for a formal timepiece should you forget to take it off on your way from the dive site to the evening gala (which is a real problem for me, I’m always in such a hurry rushing from my private yacht to those pesky evening balls…gosh life is hard being a secret agent! Ahem, I mean online journalist…yeah, just a normal, run-of-the-mill journalist…).

I have always tried to keep my dive watch and dive computer separate, I enjoy having the redundancy of two time keepers and it gives me an excuse to purchase two individual wrist adornments! It’s strange though, because of late I’ve been more and more enticed by the lures of a combo watch-dive computer. I don’t think it’s because I am actually keen to buy a watch/computer, I think I’m just so impressed by the different ways that watch manufacturers are able to overcome the technical and spacial constraints that are innate when attempting to engineer that much technology into such a small package. The real problem however, is not that they can’t fit the computing power into the little unit, but that the designers struggle to find a clear and concise way for the user to view and manipulate the information. How do you ensure that the massive amount of data that your clever little watch has collected about its environment is easily displayed on a two centimetre wide screen without it turning into a solid lump of black colour for those of us without superhuman eyesight? The answer, my friends, is that you don’t just use the digital display…you use the watch hands too!

Tissot Sea-Touch: Features

I am going to warn you now, you should ensure you swallow your food and drink fully before you read the rest of this article, otherwise you risk covering your computer in juice and sandwich – you will spit it out in awe of this James Bond watch!

Coffee Swallowed? Good, Because This Watch Will Blow Your...Em...Hat off!

Analogue Hands: For More Than Just Time!

This ingenious watch from the country that brought us the Swiss Army Knife (Switzerland…for those of you that are reading this in the morning and haven’t had your coffee yet) has managed to fully impress a jaded gear-junkie that thought he’d seen it all. In terms of information presentation I was sure that the best any designer would ever manage would be to increase the resolution on digital displays so more information could be displayed, I never though they’d use the mechanical hands to display the data!

There are a few watches out there at the moment that have a mechanical depth gauge built into the facia which adds an element of scuba chic to any outfit, but doesn’t really do much more than provide a minor element of convenience and back-up redundancy for your standard pressure gauge. The Sea-Touch however, uses the two hands from the analogue watch and electronically swivels them to correspond with the appropriate markings on the bezel. Watching the hands of a watch quickly and smoothly rotate to certain points on the facia was cool enough to have me drooling over this piece of Swiss magic!

The Hands Swivel Quickly To Point To The Setting You've Just Selected, Which Is Extremely Cool!

A Bloody Touch Screen!

The Sea-Touch is the aquatic member of Tissot’s “Touch” collection of watches. They are all well built and robust watches with a very impressive party-trick – in addition to having three conventional pushbuttons on the side of the watch, the glass screen is touch-sensitive as well! It’s not touch sensitive in an iPhone sort of way (with a computer screen and icons), instead there are clearly marked areas for you to touch around the outside of the dial that, when touched, will change the watch mode. Even the centre is touchable, adding further functionality to the menu system.

The touch system is remarkably un-gimmicky because there is a very restrained air of practicality and functional design. It’s as though the designers wanted to impress us with the capabilities of the product rather than the lights and fanfare that usually obscures functionality on electronic devices…what a novel idea! The screen itself is unmarked, because the touch sensors are somehow invisible (more voodoo). The touch aspect can be switched on or off to ensure that you don’t end up launching a missile somewhere or deleting the national bank records by accidentally bumping the watch off your thigh.

Amazing Touchscreen, Refined Yet Practical

Dive Computer

The Sea-Touch is a peculiar instrument because it has all the features of a dive computer, and yet the manual recommends that you dive with a separate dive computer because the Sea-Touch is only to be used as a back-up. I believe this is because Tissot have realised that the watch’s instruments are not nearly as precise as a fully fledged dive computer, though I must confess that if I had the chance to own one, I’d almost certainly use it for day-to-day diving, and only take my proper computer for deep dives.

Tissot have been very clever with their use of the rotating hands as they’ve managed to employ them to display the two most important pieces of information when on a dive; the depth and the ascent/descent rate. On the outside of the bezel is the depth (denoted in meters or feet, depending on what model you buy) which the minute hand points to, and on the left side of the facia there is a scale of metres per minute which the hour hand uses to state your speed as you move vertically in the water. The depth gauge is marked in such a way as to give you more precise readings for the first fifteen meters, any deeper and it becomes less easy to define your precise depth.

The digital screen is not left out of the action as it provides the diver with the elapsed bottom time in hours and minutes. This dual format display allows the diver to quickly glance at the information they want, rather than scrolling through digital menus or trying to decipher which number means what.

The log book is necessarily simple, though it covers all the aspects that you really need. It can be a little frustrating accessing it, with limited display to aid your navigation, but with a little time spent with the instructions you’ll get the hang of it. Obviously the memory is much more limited than a dedicated dive computer, but it is more than sufficient for the average diver.


This is a really innovative feature that I am so impressed with because, unlike most other dive computers that have an integrated digital compass, the Sea-Touch’s compass is actually worth using. Instead of displaying a crappy digital heading on a screen, the Sea-Touch uses a very familiar and effective way of displaying north – it points an arrow towards it. To put it simply, Tissot have integrated a digital compass into the computer but instead of using the digital display to show where north is, they use the minute and hour hand to make a long arrow that swivels just like a conventional fluid-filled compass. This is a feature that really has to be observed to be really impressive, but by using the physical hands to display direction Tissot have managed to overcome the nasty and lengthy “relearning process” that most divers have to endure to be able to operate their digital compass effectively.

Dive Mode Is Automatic (@ 1.5m) And Can Be Manually Set For Snorkelling.


Like all good electronic devices, you can always make it more desirable by adding a thermometer, the Sea-Touch is no exception, and it becomes especially useful when you are diving (a dunk of the wrist in the sea will let you decide what exposure protection to wear before you get in the water).


Build Quality – The Tissot has a very reassuring weight to it which provides an immediate sensation of robustness. It is a solid timepiece that will endure several years of diving flawlessly. There's A Whole Lot Of Metal In This Watch, Which Reassures Me...

Ingenious – There are many people who will decry this watch as a gimmick-laden toy, but I see real, functional design that has finally managed to push the boundaries of how we interact with our watches.Easy To Read – This is a big draw for some folks who hate digital displays. The hands are big and defined which allows for quick glances rather than extended reading, which is handy when you’re on a tricky cavern dive! The Excellent Display Is Made Even Better By The Backlight.

Full Featured – This watch packs more features than a huge range of other dive-orientated watches, and yet it somehow remains a viable dinner timepiece. Truly an exercise in exceptional design.Excellent Compass – I am very disappointed in most of the integrated digital compasses that are on offer with dive computers, this one however, has really grabbed my attention. It combines the size of a digital unit with the ease of use that comes from a mechanical offering, with very little drawbacks!


Price – So, all these features will be cheap will they? Um…no…sorry. This is a seriously expensive item of gear that will be far beyond most diver’s pockets. Though this doesn’t bother me in the slightest because things like this are not meant to be owned by everybody, they are meant to inject excitement into the atmosphere when it turns out a diver has one on the boat – it is a spectacle to behold like a Ferrari or a pair of Prada shoes at a party. Watching one in action makes my mind boggle, which is precisely the effect it’s meant to have.Accuracy – As mentioned above, there are small issues with the accuracy of the instruments (especially at extremes) which Tissot have warned might make it unsuitable for using as a solo computer, though for the average diver it is more than sufficient (who needs to know how deep they are to the centimetre anyway?).Depth – This is a two-fold criticism because the Sea-Touch is waterproof to one hundred metres which makes me a little nervous (I know divers that have dived to seventy metres on air…which is a little too close to the watch’s maximum depth for my liking) and the depth gauge is only marked to fifty-nine metres which means that it is only suitable for recreational divers – Tec divers will have to look elsewhere.

Final Thoughts

I’ve pathetically gushed enough for you to realise that I am thoroughly impressed by the features and design of this watch. It has made me reconsider what other manufacturers are offering and has raised the bar for ingenuity in wrist-top computing considerably. I hope to see a more hardcore version of this watch come out in the near future, regardless of price, because ultimately I’ll just be reviewing it…not buying it!

Deep dive: an introduction

Why Go Deep?

Diving manages to collect a massive variety of very different people together into one category: divers. Diving is a sport to some, to others it’s a hobby. I’ve met divers who are in it because it helps them keep fit and I have also met people who dive purely to escape their spouse’s nagging. Diving offers all this and much more to many people, but there is one thing that almost everyone takes from the pursuit – the peace.


I have never met a diver who dislikes the fact that the only things you can hear when diving is your breathing and your bubbles, for some it’s the reason they dive (I have a friend that dives in zero viz regularly purely so she can enjoy her bubbles). I have even heard diving compared to meditation in the way that it makes you focus on your breathing and your body. I feel the same way to an extent, I really enjoy the relaxation that comes over me from breathing slowly and deeply, doing an almost yoga-like swim and looking at relaxing images. I feel this most strongly when I go deep. The deeper I go the more intense the feeling of solitude and of contentment. This comes from a number of things but mostly I enjoy the sensation of getting narc’d (more on this later) and the fact that sound becomes more remote the further you descend, to the point where I feel almost disconnected from my body.

The Sense Of Solitude At Great Depths Is Humbling And Addictive.


Ok, enough of the hippy crap, apart from feeling really chilled when I go deep what are the other reasons for going down where it’s grey? One reason I would consider trading a long dive for a deep one is so I could explore a well sunk wreck. It is common for wrecks to be scuppered in deeper sites to make them less dangerous for other vessels sailing over the top of them. In other cases the ships simply sank, they weren’t planned events so they sometimes ended up in inconvenient places. When a diver is really keen on his wrecks he will surmount almost any obstacle to get at his prize. These guys are often extreme tec divers solely so they can sit on the bridge of a big cruiser.

The Deeper The Wreck, The Greater The Challenge!

Search and Recovery

As with ships sinking in inconvenient places, we drop or loose other items overboard when we go diving, it’s a fact of life but no less frustrating! When this happens over a deep drop-off then it falls beyond the average diver’s ability or experience to retrieve it. This is where those deep freaks become really useful as they will almost certainly delight in grabbing a lift bag and plunging down after your camera, keys or weight belt! Search and recovery is also a code term for the looters of the sea. Often those divers who were madly excited about sitting on the captain’s chair will also ensure that they take a souvenir back to the surface with them. I won’t speculate on the morals of wreck robbery, but I will say that you’d best be careful if you want to indulge your mariner’s curiosity with a heavy memento as there have been some nasty accidents with bringing bulky objects back to the surface.

The Gauges From This Aircraft Will Have Long Since Been Stripped For Trophies.


A less common reason for going deep is to go searching for different fish and life than is found at the surface. This is often a fairly fruitless endeavour because the light density at depths greater than thirty meters is not sufficient to support coral, which in turn makes the life at this depth very transitory and well spread out. It is possible to see some amazing creatures when your down deep (often large game fish will come down here for different reasons), but it’s in no way a certainty.

Drift Dive

This is an even less common reason for deep diving, but for the adrenaline junky it is a fantastic one! There are a number of predominant prevailing ocean currents that have no effect on surface waters but are very strong on the bottom. Some of these currents are channeled along a wall or drop-off which makes for a spectacular dive. I would hasten to warn novice divers away from attempting this kind of dive unless you are accompanied by an experienced drift/deep diver because navigating at these depths is tough and ensuring you don’t get caught in a downwards or upwards current is imperative!


For the average deep dive (twenty-five meters to forty meters) the equipment list looks very similar to that of a shallow dive but there are few additions that usually don’t prove necessary but they can make the whole experience much more pleasant and possibly a little safer.

Balanced Regulator – This isn’t really a specialist piece of gear these days as most mid-ranged and higher end regulators are balanced. The balancing refers to the way the first stage modulates the air pressure from high tank pressure to intermediate hose pressure. If you took an unbalanced regulator on a deep dive it would mean that as you descended it would feel harder to breathe from the second stage because the first stage wasn’t balancing the air pressure with the surrounding ambient pressure of the water.Flashlight – This might seem a little overkill to those divers who dive in clear tropical waters with nothing worse than ten meters of visibility, but even those divers might appreciate the extra light source when they get very deep. It is especially useful for examining fish or coral in detail as the colours will be very washed out at that depth (more on this later too!), and a flashlight is able to reintroduce the colour which can make an interesting fish look amazing.Safety Sausage (SMB) - I am a firm believer that all diver’s should carry a surface marker buoy on all dives. The safety sausage is a no-brainer, it makes perfect sense to carry something that packs up small that will make you much more visible on the surface, it will also make other boats aware of your presence below them which might help you avoid a short haircut from a propeller! It makes even more sense when you think how lost you can get when deep diving, so being able to signal the boat to come get you might be quite an attractive capability.Reel - The reel is a really versatile utility that is useful in a number of ways; you can use it to launch your safety sausage quickly, you can use it as a buddy line in bad viz, you can use it for wreck or cave penetration, you can use it to conduct a spiral search pattern and you can even use it to repair a piece of gear in a pinch.Adequate Exposure Protection – This is another one that is very regional specific, but in essence all I want you to remember is that in most places it gets colder as you descend, so maybe going in a little warmer than usual might help. It is also pertinent to consider how warm you’ll be when you are waiting for a decompression stop to tick over. Those stops can make you cold very quickly.Pony Bottle – This is not something that I use, but I’ve seen plenty of divers pull them out on the boat. They are very easy to use and they often simply attach to your main tank which makes them fairly convenient. The problem I have with them is that they really don’t hold much air, you might get as much as fifteen mins of breathing time on a big one but for most divers, it’s simply not likely that they will be caught out with no air and no buddy to aid them. It’s a technophile toy, but a bulky one that makes air travel costly.Dive Computer – Another item that I think no diver should enter the water without, but often diving is a spur-of-the-moment, holiday decision which leaves you without gear. For those divers I implore you to go beg, borrow or steal another computer for the dive because things like decompression stops, ascent rates and surface intervals are a nightmare/impossible to calculate on a standard RDP. Deep diving has too many variables to leave it to chance, just grab a computer and make your life much easier.Reference Line – This is a really good idea for the novice deep divers among us because if you have a line or can follow the bottom you are considerably more able to deal with equalisation problems, nitrogen narcosis and to perform adequate safety stops.  Though I must confess that I much prefer descending to a deep dive in free fall because I find it really fun – it’s like base jumping in slow motion!Safety Stop Bottle and Weights – This is sometimes called a safety stop station and is usually hung at around five meters so that divers can rest there during their safety stop. It also means that if the diver gets to the station and finds they are very low on air, they can breath from the emergency tank while they perform the stop and then ascend on their own tank. Ensure that you turn the tank on before you sink it because otherwise water will flood the first stage and damage it. Sometimes the station will have spare loose weights which are there to compensate for the excess positive buoyancy that you’ll have at the end of the dive, though I think this is cheating – just weight yourself properly at the beginning of the dive!Emergency Oxygen – This should come as no surprise to any rescue divers out there. Emergency oxygen is the first treatment you should administer to any diver with suspected decompression sickness or a lung over-expansion injury. Make sure you are familiar with its operation and that you know where it is kept – don’t rely on others to know its operation, they may be the one’s who need assistance! Using A Reference Line Can Make Your Life Much Easier!


Diving has inherent risks, this isn’t news to anyone. The risks are usually blown out of proportion by those who are not familiar with the real science of diving. It is very unlikely for a diver to get hurt while enjoying their hobby, but there are certain things that I can say with something close to certainty will hurt you if you ignore the basic rules of diving – rapid uncontrolled ascents, breath holding as you go up, touching things you shouldn’t and ignoring the dive tables. These are all well known dive dangers that most divers are well aware of and are prepared to avoid (and thus makes their dives safer). Deep diving is not fundamentally different from “shallow” diving because all the same rules apply, only they now apply a little more severely.

Nitrogen Build Up

One of the main issues with deep diving is that you take on air at high partial pressures which means it’s like breathing anything from eighty percent nitrogen to hundreds of percent nitrogen on the surface. The partial pressure of oxygen is also higher, it goes from twenty-one percent up to over a hundred percent, and has the same effects as it would on the surface if you breathed one-hundred percent oxygen.

If a gas is highly pressurised in a fluid filled container (which our body acts like) then it will dissolve into the liquid at an amount which is directly proportional to the pressure of the gas. What this means is as we descend on a deep dive, the gas pressure increases which makes it more able to dissolve into our blood and tissues. This is perfectly safe and we are able to reverse the process by simply reducing the pressure (ascending). The problem arrises when we reduce the pressure too fast by going up quickly as it allows bubbles to form in the tissues (think of the way a bottle of coke is still until we release the pressure by opening the lid – this makes all the carbon dioxide form bubbles and escape). The key is to “open the lid” carefully and slowly which stops the gas from bubbling up i.e. ascend slowly.

Deep diving loads us up with a large quantity of nitrogen which means we have to go up even slower than on a shallow dive, sometimes you will have to stop for a while at certain points (denoted by your computer) to allow your body to catch up and dump the nitrogen smoothly. These are called decompression stops and if your computer says that you require one then it is imperative that you abide by it. These are not necessary in normal shallow dives, but if you exceed your no-decompression dive time then you will need to plan for decompression stops (ensure you are well insulated, have good buoyancy and have ample air).

There is also a massive rise in the amount of schools that offer blended gas mixes or “nitrox” which is simply a breathing gas with less nitrogen and more oxygen – this means the body will take on less nitrogen and this will make for a longer no decompression dive (or shorted decompression stop).

Some Tec Guys Have Different Blends Of Gas For Each Safety Stop...

Nitrogen Narcosis

I said above that there was no issue with loading up on excessive nitrogen which is true to an extent in that there is no health hazard with the gas, though it does have a physiological effect. To put it simply, nitrogen in high partial pressures manages to disrupt and slow the neurones in your nervous system. This is not dangerous but it has some strange effects on your senses and mental capacity.

Many describe being “narc’d” as being a pleasant sensation of relaxation which has led to the name “the rapture of the deep” being bestowed upon this condition. Everyone feels different things when they get narc’d and everyone gets it at different depths and different severities. I am the only diver I know that gets my kind of narc; tingles on my skin, a pleasant sensation behind my eyes and a taste in my mouth that can only be described as a smooth creamy taste.  I don’t tend to get much else in the way of symptoms, my head stays fairly clear until I get very deep. Some people really struggle with keeping their mind clear as narcosis also impairs your mental capacity (which can be a problem if you require a cool head to attend to an emergency). The effect has been described by the “martini law” which states that diving at thirty meters is the equivalent of drinking two martinis and that every ten meters afterwards is another martini. This is a tongue-in-cheek way of looking at the phenomenon but it helps to give you an idea of the effects you might experience. The law also applies in the same way that one person might have three alcoholic drinks and be able to function nearly normally, whereas another might be singing on top of the bar after two cocktails.

Narcosis is unpredictable which makes it dangerous, check your buddy and ascend a little if you think either of you are getting foolish. Some people have gotten so euphoric that they’ve removed their regulators from their mouths because they thought they could breathe under water. Keep a close eye on it.


There is almost certainly going to be a diver in your group with a small leak coming from a piece of his gear which, under normal circumstances, is no problem at all. However, we must remember that when we dive deep the gas that is vented into the water is much more dense than at the surface. This means that a leak that will cause a tank to loose two percent of its air in sixty minutes at ten meters will loose eight percent of its air at forty meters. This is not a huge amount of air, but it might be necessary gas for all the mandatory decompression stops that the computer will plan for you.

The simple way to solve this minor problem is by ensuring all your O-rings are in good order, performing a thorough buddy check at the surface and by performing a “bubble check” at a couple of meters as soon as you submerge. This involves each diver in the group slowly rotating full circle and the other divers watching to see if any small bubbles are escaping. If there are bubbles then at least you won’t be too far from the boat or shore to quickly jump out and install a new ring.


This is a triple tip (value for money!) because visibility is affected in three different ways when you go deep:

First, natural light becomes increasingly less vibrant as you descend, this is because the water absorbs the light, so the more water – the less light there is. What this means is that when a diver goes very deep he will find the water becomes very dark and he will appreciate his flashlight, especially if he wants any chance of looking into a cove or hole.Secondly, this light absorbing phenomenon does another trick because it doesn’t just soak up the light equally, it works through the spectrum from the lowest frequency (red) through to the highest (blue). What this means is by the time the diver has reached twenty-thirty meters or so they will not be able to see the colour red by natural light, it will appear grey. This can be combated by flashing your torch on it because the torch light still has all its red in it’s beam.The Third way in which viz is affected when you’re deep diving is from the sediment that deep sites often have floating in the water which can lead to a very short sight range. This is not universally true, but it is often the case that the first fifteen meters of a dive site are clear and then you hit a soup layer than reduces your viz from twenty meters to two meters. This can hamper navigation somewhat and would be helped by a light to pierce the sediment (sometimes) and by relying on your compass. The Water Gets Blue And Dark Down There, Get A Good Flashlight!

Final Thoughts

Deep diving is a real pleasure that gives me a fantastic feeling of excitement before I go down and tangible feeling of relaxation as the sound of my bubbles dies away (the water pressure makes the sound echo much less, so sound becomes quieter and more remote which is very pleasant). It is also a key to many difficult to access dive sites and wrecks which makes it a valuable skill to learn. The important thing to remember is that deep diving is a skill, which means it takes practice and tutoring to dive deep safely. Pay extra attention to the basic rules and learn how to use your equipment intuitively so that the only thing you need to think about when you’re down there is the silence.

Diving in Marshall Islands

Who, Where and What Are the Marshall Islands?

The Republic of the Marshall Islands (RMI) is an island country in the North Pacific ocean. It is often simply grouped with the other island countries in the area as Micronesia. The country is made up of five high islands and twenty-nine atolls that roughly form into two strips. There are around sixty-five thousand inhabitants on the islands and they rely primarily on fishing for their industry.

These Really Do Contest For One Of The Most Beautiful Places In The World

For the traveller: you’ll be spending US Dollars when you’re there, and it’d be wise to take mostly cash and some traveler’s cheques because cards are still a novelty out there. Getting there can be achieved by boat or plane, though both are expensive and awkward forms of transport since the shuttle flight service that ran from Australia to Majuro (Air Nauru) was cancelled due to soaring energy costs. Once you’ve arrived you’ll mostly be speaking English, although the natives will speak a mixture of Marshallese and English to each other.

Why Should You, As A Diver, Care About the Marshall Islands?

Because the Marshall Islands is easily one of the best dive spots in the world for both wreck diving and natural diving!

The fact that it is such a pain in the neck to get to has meant that the islands and atolls are relatively unspoilt and are massively diverse with flora and fauna. The dive sites are almost unparalleled in their untouched beauty, and can be seen with great clarity due to the consistently fantastic visibility underwater.

Breathtaking Views, Perfect Conditions And Diverse Wildlife...Paradise!

The main reason that a diver cares about the Marshall Islands, and the Bikini atoll (the swimsuit was named after the island, not the other way around!) in particular, is because of the astounding wreck diving on offer. In the early days of nuclear weapons testing the US found a remote spot in the pacific (that was inhabited, but the locals were shooed away like pests… don’t get me started on a rant!) and bombed the crap out of it with no regards to the wildlife or the fact that this was where people lived. The small plus side was that the Americans had wanted to test the effect of these super weapons on war vessels and had placed a mock fleet in the blast area. Luckily, for divers, a lot of these sank and left us with a lovely sunken fleet to explore. Included in this roster of wrecks is the USS Saratoga which is the only “divable” aircraft carrier in existence. Make sure that you’ve done a few deep courses before you head out though because the good stuff is pretty deep and will require you to go outside normal recreational dive tables – I’d advise you do a nitrox course and get at least a hundred dives under your weight belt before setting off for the Marshalls.

About The Radiation

The Bikini Atoll has had over 75 megatons of atomic bomb blasted in and around the lagoon which has left its legacy. According to recent studies, there is a build up of caesium in the soil which has been passed into the coconut trees and the surrounding food chain. This caesium is not immediately dangerous to humans, nor is the background radiation, however the studies found that living off the land and ingesting enough contaminated coconut and other food stuffs down the subsequent food chain would certainly lead to medical consequences. The upshot is that you can visit the Marshall Islands and Bikini Atoll with relative safety from radiation sickness (the background radiation is lower than that of London or New York), just don’t eat any local produce!

Looks Amazing, Is Actually A Tragedy...

The Wrecks:

USS SARATOGA – Easily one of the most recognisable names in wreck diving, and certainly one of the biggest dives on the wreck scene! She is around two-hundred and seventy metres long and weighs in at thirty-three-thousand standard tons! The Saratoga is brimming with weapons, dials, armaments and other goodies to look at, and it is the most easily accessed wreck on the Bikini atoll because, despite the wreck sitting at around sixty metres, the top point is only thirteen metres below the surface! The Saratoga is a delight to dive on and can be enjoyed by most levels of diver because of the vast differences in depth and penetration available. The Saratoga is the Marshall Island’s biggest attraction and can be dived on at least four times without repeating any section! A Magnificent Ship And A Great Wreck!

HIJMS NAGATO – This is another beast of a wreck, in scope, challenge and rewards. It was the largest warship ever constructed in its day and offers a stunning dive around its huge gun emplacements (they are the biggest guns you will ever dive on!) and massive hull. The ship is two hundred and fifteen metres in length and weighs in at a vast thirty-eight thousand tons! You will have to get used to me putting exclamation marks all over this article because this thing is a magnificent piece of kit…! The wreck lies at around fifty metres deep and is inverted because it was top-heavy. Luckily the ships superstructure props the vessel up and allows divers to fully explore the deck with its massive sixteen inch guns whose barrels are over fifteen metres long! You can dive the bridge, despite it not being part of the ship anymore as it detached while sinking and settled next to the hull. With Its Preposterous Tower Bridge It Was Destined To Land Upside Down!

USS ARKANSAS – Another big boy here, the Arkansas was fitted as a capital ship which meant bigger guns and more swanky quarters. The ship weighs in at around twenty-three thousand tons and a hundred and seventy metres long. She was classed as a dreadnought battleship and was initially employed in the first world war. The ship is lying upside-down in the bottom of the Bikini lagoon which means it is around fifty metres deep but the interesting things start at around thirty metres. The hull is completely smashed and crumpled which, added to the coral that lives on it, is quite a sight to behold!USS PILOTFISH and USS APOGON – These are the only submarines sunk at the Bikini lagoon and are both in excellent condition. The two submersibles are in upright position because they are designed to sink in such an orientation. Neither of the subs are particularly big, the Pilotfish is around a hundred metres long as is the Apogon. They are both excellent dives for wreck enthusiasts, but they also have a good covering of coral, both soft and hard which entices wildlife into the area. Because of their relative diminutive size, they are ideal for diving in one session. Penetration of these wrecks is nigh on impossible.USS LAMSON and USS ANDERSON – Both of these ships are well armed destroyers and are both around a hundred metres in length. The Lamson has a massive plethora of toys to examine in the form of countless guns and cannons, they are easily spotted too because the ship is sitting upright, unlike the Anderson.USS CARLISLE and USS GILLIAM – These are attack class transports are both extensively damaged, especially the Gilliam which has suffered catastrophic midship damage. They have a little less in the way of guns and placements to examine but they are still brimming with things to see, especially when you below deck and explore their hangars.HIJMS SAKAWA – This is a Japanese cruiser that took serious damage from the blast being as it was placed in the direct vicinity of the bomb epicentre. It sunk on the first explosion.

The Sites:

The Marshall Islands are not just a wreck diving paradise, they are also fully fledged aquatic gardens of Eden. The reefs are full of life and are well worth diving independently from the wrecks.

Bikini Atoll

At the Bikini Atoll itself there is a world famous dive site named Shark Pass which is home to grey reef sharks and silvertip sharks. The reef is also packed with a variety of soft and hard corals, Jacks, tuna and napoleon wrasse.

The Bikini Lagoon Is A Wonderful Oasis For Tropical Fish

Majuro Atoll

The Majuro Atoll is a varied dive with depths ranging from only three metres right down to around thirty-five metres. There are coral pinnacles which are home to small reef fish, and further out you will see some Pacific ocean cruisers looking for lunch!

Mili Atoll

Another feature packed dive site that will amaze divers with manta rays and sharks, and keep them busy in the mean time with giant clams. On the surface the birdlife is remarkable.

Grey Reef Sharks On The Prowl...

Rongelap Atoll

This has all the usual suspects as you’d expect from a Pacific, equatorial dive site but there is a little twist; the dive site is in perfect, pristine condition having been in true isolation for fifty years. The water is crystal and the wildlife is untouched.

Go Exploring!

There are many mapped and well-dived sites in the area that you can be guided around and you will surely enjoy it, however there are many other wrecks and reefs in the area that have never been dived before! That means that the true explorer in you will be fully sated, just talk to the local dive schools about making a trip further afield to fully embrace the underwater environment.

Final Thoughts

When I write about the Marshall Islands I always wind up torn and confused. On one hand I am so grateful that these amazing wrecks and reefs exist in such a paradise on Earth, yet I am also gravely depressed and angered at the atrocities that have befallen the local populace in the name of war machine refinement. It is a double edged sword that cannot be easily dealt with, but I urge you to visit the islands and to come to your own opinion. By supporting their fledgling diving industry we can each do our part to help rebuild their infrastructure.

A review of three modern diving knives

Function Over Beauty

I like a dive knife that looks great, we all do! However,  a sexy looking knife is not much use to you if it doesn’t cut through that mono-filament line that’s wrapped around your leg! I tried three modern knives out on an assortment of materials that commonly cause diver’s trouble, from fishing monofilament to three-strand anchor line to high-tech cable-strength braids. I also subjected them to a “corrosion test,” an extended period of aquatic abuse in a saline solution to see how well they resisted rust and corrosion. Each knife was dunked in saltwater three times a day for a week. Between soaks I set the knives out to dry while still in their sheaths. At the end of the cycle, knives and sheaths were inspected. In general, the titanium and higher  calibre stainless blades were the most resistant to corrosion, while the softer 304-grade stainless knives showed less signs of rust than the harder 420-grade stainless knives. No rust spots were so imbedded that they couldn’t be buffed out with a cloth. The important thing to note here is that a decent maintenance routine will keep a modern dive knife looking new for as long as you can bear to not buy a newer, sexier knife!

Riffe Silencer

Full knife length: 9 in.

Blade length: 4.5 in.

Blade: Plain edge and serrated edge combination.

Metal: 420 stainless steel.

There Is Something About A Stiletto Blade That Just Means Business, And This Blade Means All Sorts of Business! Mostly Cutting Business Though...

The Silencer is made of hardened (heat-treated) 420 stainless steel and has cutting edges sharp enough to cut virtually anything. The 4.5-inch stiletto blade, which is Teflon-coated to prevent rusting, offers a plain edge on one side and a wavy serrated edge on the other, giving you a choice of cutting surfaces. The over-moulded handle has an ample blade guard for a safe and secure grip. It also offers a tool built into the end-cap to remove spear shafts that get wedged in rocks. The sheath comes with a pair of rubber leg straps and offers a locking push-button release. An elastic lanyard attaches to the end-cap for extra security.

The Silencer’s blade, with three inches of serrated edge and four inches of plain edge, proved to be the best all-around cutter in this review. It was the only knife able to slice through every type of test line–even the Amsteel–with a single pull, and it did it with both edges. For spear fishermen who can get wrapped in their own line during a hunt, this is the Silencer’s strongest selling point. But the sharp stiletto point is a winner too, designed to quickly dispatch a struggling fish. While the blade is Teflon-coated to prevent rusting, the cutting edges aren’t, so by the end of our corrosion test, the Silencer was showing a couple spots of rust; however, they all rubbed out with a towel. The Silencer’s sheath is one of the best we’ve seen. A sliding safety mechanism prevents an accidental push of the push-button release. The safety and release button are both easy to operate one-handed, and the elastic lanyard can be stretched over the sheath for added security. Standard rubber leg straps have quick-release buckles and can be replaced with optional forearm stretch-straps for a closer reach.

Scubapro White Tip

Full knife length: 6 in.

Blade length: 2.5 in.

Blade: Plain edge and serrated edge.

Metal: 304 stainless steel.

Back Ups Are Important, So It Needs To Be Almost As Effective As Your Primary, The Guys At Scubapro Agree With Me!

A backup cutter should be compact, and the White Tip is certainly that. Only six inches long overall, it comes with a 2.5-inch blade offering an inch of serrated edge, an inch of plain edge, and an angled tanto tip that’s nicely blunted right at the end. The blade and handle are made from a single length of 304-grade hard-tempered stainless-steel–the handle portion is over-moulded to provide an easy grip. The sheath offers a push-button release that keeps the knife secure until needed. The White Tip comes in a kit complete with hardware to mount on a console hose or BC pocket (this requires punching holes in the material). The sheath also has slots for threading a pair of rubber straps for mounting on an arm or leg. For added security, there’s a hole in the handle for a lanyard.

The White Tip offers more mounting options than any other knife in this review, making life easy when deciding where to strap it. Removing the knife from its sheath is also easy–the push-button release can be activated with one hand. The partially blunted tanto tip takes some of the apprehension out of returning the knife to its sheath, and a solid-sounding click lets you know the knife is locked in place. Because of its 304 stainless blade, which doesn’t hold an edge as well as harder metals, and its short blade length that offers less cut per pull, the White Tip was not the most efficient cutter of the group. However, it was able to eventually cut through our entire inventory of test lines, taking only a couple pulls to get through the lighter lines, 10 to 18 pulls on the heavier lines, and 25 pulls on the Amsteel. It did a good job of resisting rust; after a week of repeated saltwater dunks it showed no signs of tarnishing.

It always makes sense to carry a backup cutting tool, especially one that’s compact and doesn’t clutter up a dive rig. We like the White Tip’s ability to bolt to a hose, a strap or a BC. But if none of these options suits you, the White Tip is so small it will probably fit into your BC pocket.

Spyderco Aqua Salt

Full knife length: 9.25 in.

Blade length: 4.5 in.

Blade: All plain edge or all serrated edge.

Metal: H-1 stainless steel.

A Mean Looking Knife, A Really Hard Worker And A Solid Bit Of Kit.

This knife is not to be trifled with. Its blade has a lethal point and comes with either a scalpel-sharp plain edge or a seriously serrated SpyderEdge (a pattern of one large and two small serrations) backed by a full-curve “belly” that produces very effective slicing-type cuts. The blade is made of rust-free H-1 stainless, a special composite exclusive to Spyderco that uses nitrogen in place of carbon in its steel matrix. This maximises corrosion resistance while still enabling the blade to hold a sharp edge. The handle is made of textured, fibreglass-reinforced nylon. The heavy-duty Kydex sheath is riveted for strength. It secures the knife with a friction lock and features a G-Clip belt fastener that can be configured in five positions to suit your diving style. The Aqua Salt is available with either a yellow or black handle with a hole for a lanyard.

Both plain edge and SpyderEdge versions of the Aqua Salt were able to cut through our inventory of line, though the serrated version had an easier time doing it. The full-sized handle let us grip and rip; while there’s not much of a blade guard, the textured handle and finger grooves keep hands from slipping forward. We cut all test line with a single pull except for the Amsteel, which took five pulls. The H-1 blade excelled in the rust test, showing no signs of corrosion on the blade and only a slight bit of tarnish on the engraved “H1? logo, which rubbed right off. The G-Clip belt fastener fits securely on a standard two-inch harness strap, and the sheath’s grommet holes offer cable-tie attachment points for added security. One-handed removal is accomplished by pressing your thumb against the top of the sheath. The large mouth makes an easy target when returning the blade home, which clicks when the friction lock activates.

If you’ve always had a hankering to take your sharpest chef’s knife diving with you, leave it in the drawer and take this one instead. Of the two styles, we prefer the serrated version for its better cutting efficiency. But neither style disappoints. A bit of advice: Mount the sheath where you can see it; a near-miss when returning the blade home can get bloody.

Final Thoughts

Knives have come a long way since the huge swords of yesteryear, they were a little impractical but were most likely a psychological crutch to distract them from the fact that their gear was far from fool-proof and the site they were diving on was unexplored. Today’s divers value efficiency and lightness and the three knives I reviewed above provide exactly that. The new, corrosion resistant and hard blades, combined with easily gripped handles and secure, convenient sheaths have revolutionised dive safety knives and have made choosing your next blade even more enjoyable!

Computer Vs. Tables
I tap my air gauge to indicate that I’d like to know my buddy’s air situation, he signals back that he’s still got over a hundred Bar, I look at my gauge and see that I’m also over a hundred, so I signal that we could head a little deeper to investigate the ship’s lower decks if he wanted to – they didn’t look that interesting on the dive map so we didn’t plan for them, but from down here they look very inviting – my buddy agrees with me and gives the “ok”, so we descend…

The situation described above is a fairly normal situation when diving a site you don’t know. You may have looked at maps of the site, but ultimately you won’t know where you want to go until you’re down there. The problem with this is that if you don’t know where and, more to the point, how deep you wish to go then your planning on the RDP (Recreational Dive Planner) counts for very little because it will constrict you to an inflexible dive profile that might not meet the type of dive you want to do. For the guys described in the passage above they would be diving beyond their scheduled dive plan which could cause them real problems once they surface.

The modern diver doesn’t interact much with the RDP these days. The closest most divers get to using the tables is during their open water course, or their nitrox course, and even this will come to an end soon (PADI will be phasing in the computer-only open water course in the next couple of years). And yet, for all that a novice diver will think he is not using the RDP, he will be using it every time he dives, because all dive computers use the tables for their basic model. In essence, the computer is just an electronic RDP calculator with a depth gauge, stopwatch and memory all combined into one unit. There is no ground breaking technology in it, yet it is the most researched and refined piece of gear you will find in your equipment bag.
 Still Used In All Dives, The RDP Lives On In Computers Rather Than Slabs Of Plastic...

So Jamie, How Does It Work?
Em… ahem…you see…there’s a gauge right, and a…a…and it’s very complicated, you wouldn’t understand it!
Although it is very complicated (for the designers), it is also very simple (for us, the users). As the diver begins his descent the computer starts the stopwatch, this is the actual bottom time. It also begins to take readings of depth at frequent intervals (usually around twenty a second, though you can normally set it to be more or less often). For each reading it takes, it gets its tiny RDP out and does the calculation just as we do in our open water course. It then jots down the current nitrogen level in our body and also states how much more bottom time we have left at this depth. If we stay at this depth the computer will keep doing its RDP sums and count down our bottom time, if we descend further it will see that we are deeper and start doing maths to find out how much less time we have. So basically you have a little man inside your computer who is crazy fast on the ol’ RDP and he does constant and corrective calculations that give you an accurate statement of your current levels of nitrogen and how much longer you can stay at that depth…. Does that sound plausible?
 You Feed The Little Man Through The Tube On The Left...

Which Computer’s Best?
Obviously everyone wants to know which model is best, to save them buying a duff product. The odd thing about dive computers is that, even though there are certainly “better” products, the actual dive computers are mostly all the same or similar. The real differences between them are how they display the information, how easy they are to use, how it looks, and what additional features the designers have managed to squeeze in. The computer’s ability to calculate remaining bottom time is generally fairly standard nowadays (with mild variations in accuracy, the mathematical model used and how conservative they are).
The answer then, is that none of the computers are better than the others, but there are plenty of reasons that you’d choose one computer over another. I’ll look into what those reasons might be throughout the rest of this article.
 Take Your Pick...All Computers Ultimately Aim To Do The Same Thing!

What Does It Mean If My Computer Is Conservative?
It means your computer believes in marrying before having sex, and thinks knee length skirts are too short! Well, not really, most computers are actually very liberal and into free love and support progressive government propositions!
But in a diving sense (which is why we’re here after all), a conservative computer is one that will either give more warnings, give warnings earlier or read as though you have been deeper or have less bottom time. To put it simply, a conservative computer is a very nervous, safety conscious computer that would like to err on the safe side rather than take risks. This might sound like exactly the kind of computer you’d want, who wouldn’t like to be more safe on their dive? The answer here is that an overly conservative computer will likely drive you to insanity before you’re more than ten minutes into the dive. A twitchy computer will beep if you move your arm up too fast, it will make you do double the safety stops your fellow divers will do and you’ll end up loosing a big chunk out of your bottom time.
The key is to get a computer that has variable levels of conservatism so you can set it to a level that suits your circumstances (if you are very overweight, for instance, it might be prudent to put the computer on a more cautious setting).

Wrist Vs. Console
This is a less pressing debate now than it was ten or even five years ago because computers of today are much more compact, so there is less of an issue putting it on your wrist as it was before.  It is less a piece of gear, as a very functional piece of jewellery.
The question is, do you want the convenience of having your computer built into your regulator (usually in place of a SPG) so that you can’t forget or loose it, and you get the added benefit of having air readouts and calculations displayed on the same screen. Or, do you take the lighter, more easily read and more fashionable watch-style computer that now has the ability to take air readings too (in some cases)?
The question isn’t as pressing as it once was, but the customisation of gear is the mark of an experienced diver, and this is a personal choice that will make a tangible difference to the way you interact with your computer.
 Which One? Doesn't Matter As Much As It Once Did...

Essential Features
This is a short list of the features that most modern dive computers come with as standard, you can use this as a glossary of terms so you know what you’re looking at when staring at the back of the box in the dive store.

Clear Display – This is pretty much priority number one for me, if the screen is jumbled, illogical or too small then I will not be able to fully interact with the computer on a natural level. The computer must be able to plainly display all the information you need throughout the dive in a basic and concise format. Avoid busy screens, choose a large, simple display.  As Screen Technology Gets Better, The Displays Can Show More - Colour Screens Are The Next Trend

Intuitive Menu System – For similar reasons as I require a logical screen setup, I need to be able to select functions, view different data and adjust settings in a coherent and rational manner. Again, simple menu systems work better for this than ten button, IQ test, Rubix Cube puzzle systems. 

Alarms – When you’re diving you’re down there to experience the underwater world and see as much as you can, you certainly don’t want to be diving with your face attached to your computer screen. This is why alarms are useful, they will tell you if you are reaching maximum bottom time, your predefined time limit or ascending too fast. Alarms let you dive, not watch a screen underwater. 

Backlight – Simple, you want to see your computer on night dives and in bad viz? Get a good back light that will operate for long enough to let you fully read the display. 

Comfortable – You will be wearing this wrist-top computer for at least two hours on the day you dive, and if you’re like me you’ll leave it on between dives. Make sure you test how comfortable it is (some are really bulky and very uncomfortable). 

Thermometer – It might seem like a frivolous feature that is only for curiosity’s sake, but a thermometer is useful for lots more than just telling your friends how cold it was on your ice dive! A thermometer can help you work out your temperature tolerance (look in the log book, see that last time you dived in twenty degrees you wore a five millimetre and you were cold, now you know to take a seven millimetre suit) or it can give you an idea of what wildlife will be around, or not. 

Ascent Rate Indicator – One of the most used features on a computer, this monitors how fast you go up. If you go too fast it will warn you so you can slow down. This is great for letting you relax as you ascend, if the computer is reading green then you can just enjoy the last of your dive, not stress about the ascent. 

Safety Stop – Another important feature of a computer is to alert you to mandatory and non-mandatory stops, at what depth and for how long. It will give a countdown and an ideal depth for you to rest at. There will be another alarm if you ignore the safety stop and it will send you to bed with no dinner (a computer can be a real nag!)

Desirable Features
This is a list of things that you might be interested in looking out for when choosing your next computer. Some are more useful than others, there is a fine line between throwaway gimmick and essential tool.

Air Integration – I briefly mentioned this earlier, essentially it allows your computer to monitor your air supply and not only display how much you have, but how much more time you have left breathing at the rate you are presently and the current depth. The accuracy of this is a little dubious and for most divers it is unnecessary because they can calculate their own air supply. If you are looking at using air integration with your wrist computer then you will need to buy a separate wireless transmitter that attaches onto your regulator first stage. These little devices can cost a fortune! The value of such an item is very subjective.  Air Integration Can Add A Lot To Your Dive, And A Lot To Your Credit Card Bill...

Compass – Compasses in dive computers are both potentially useful and generally pointless. The fact that you can house a digital compass in the computer is very exciting, and as a backup it’s great. But, the format that it is displayed in is so unnatural that I always end up reverting to my Suunto and working old-school. Once they manage to get the display of the digital compass to equal that of an analogue compass then this will be an excellent feature.  The Digital Compass Is Currently Just a Backup, Hopefully They Can Make It A Replacement...

Large and Useful Logbook – This isn’t so much a feature as a general requirement. All computers have a logbook but some are hard to use, hard to read and are too small. A logbook should be something you briefly look at, recall the data and put away, not spend an hour mining the information out piece by piece. It should also be big enough to store a two week dive holiday’s dives (at least forty hours worth in my opinion) 

Gas Switching and Nitrox Support – This feature is becoming more essential as time and the dive industry progresses. It is also becoming more prevalent in the average computer, it is almost a standard feature now. Because divers now dive breathing gas blends and more than one mix of gas there is a need for the computer to work using different parameters. If this gas switching and mix entering is easy then it makes a complicated thing very simple, which is a good thing when divers are concerned. 

Computer-to-PC Connectivity – This is another trend on the marketplace that will only become more common, not less. People are used to uploading and downloading their personal information onto the computer and internet (look at what we do with our personal digital pictures and what we write about ourselves online). This goes for dive logs too. A dive log program will display graphs of dive profiles and maps of dive destinations, and it will also allow you to post your dives online, for all the community to see!  Plug It In And Post It To The Internet! That's The Modern Diver's Motto!

Final Thoughts
The dive computer has now been around for so long that it is no longer a luxury item that only wealthy and experienced divers used. Even divers on a budget can now buy high quality, feature-packed computers from well known brands – they’ve become that mainstream. This isn’t a random act of capitalism at work here, it’s a simple case of supply and demand – divers like having the freedom to adjust their dive profiles on the fly without having to worry about DCS creeping up on them. They also like having control over their data, and the computers that are coming onto the market are offering them new ways to manipulate, record and view their dive information. It’s the electronic age and diving is no exception!