How To Buy a Wristwatch: Part 2- The Dive Watch - Amended Jan, 2024

EDIT: January 27th, 2024 : I've replaced pics where the links are broken or the original authors have removed them. Many thanks to those whose photos I have used here. I have tried to attribute them all to their respective owners, but if you feel that you'd like them removed, please get in touch and I'll take them down. 

Also, I've made a tweak or two to a couple of paragraphs, in the interests of clarity.  

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Okay, so I've tackled the dress watch. That style of wristwatch was perhaps the most sought-after by a majority of male customers, based on what I saw.

Although...a greater number of men under the age of around 35 to 40 were coming into my store wanting something a little more robust. A little more sporty. A little more 'youthful'. The idea of a dress watch for these guys filled them with images of their Fathers and Uncles. They viewed a dress watch as "an old man's watch", and one that was for a previous generation. This was a comment that was most often directed at something like a Rolex DateJust. 

Poor, young fools.

Anyway, this post is about a different style of watch that first appeared sometime in the early to mid 1950s.

Oh, before I go on, I just want to restate (like I did in my dress watch post) that the views, opinions and technical info in this post are my own. As I stated previously, I'm pretty certain that a trained watchmaker will know much, much more about what makes watches tick (yeah, I didn't wanna go there, either, but it's the most expedient phrase), so please view my technical know-how as very basic and simplistic. As I've said before, over the years, I've had to distill complicated technical explanations into one or two sentences in order to get a concept across to some customers.

Again, some (or all) of what I write will differ to what you might read on a professional watch blogger's site. That's cool.

And again, I will mention that I'll be using photos taken from the web and will list picture sources wherever possible. Thanks in advance to all sources. If there is no photo credit shown, chances are it'll be my own photo.

And so, Dive, dive, dive!!!

THE DIVE WATCH  

Okay, where was I? Oh yeah, so, the dive wristwatch style first appeared in the early to mid 1950s. Nineteen Fifty-Three, to be precise. But let me step back ten years to 1943. That was the year when legendary French explorer/film-maker/conservationist/scientist/inventor Jacques-Yves Cousteau first developed the Aqua-lung, in conjunction with fellow Frenchman, Emile Gagnan, an engineer. The Aqua-lung, as you may know, was the first version of the SCUBA tank which is in use today.

 

Now, there had been a few watches manufactured for diving use. A notable model was the Omega Marine, which was first designed in 1932. 

Picture of this vintage as is from;

https://www.thenakedwatchmaker.com/blog/2021/11/26/the-omega-marine-the-worlds-first-dive-watch

 

Yes, it looks nothing like what we've come to regard as a diver's watch, but this wristwatch was water-tight enough to be used by professional divers back in the early '30s. As you can see, the case was made up of two separate parts that slotted together. One part consisted of an outer case and the other section was a smaller case which housed the movement, dial and winding crown.

However, Rolex had already produced its 'Oyster' model as early as 1926. The following year, they famously put one on a lady named Mercedes Gleitze, who wore it (on a ribbon around her neck) while swimming across The English Channel. It was her second attempt at this crossing. She had already done it a few weeks previously, but her record was beaten a few days later, so she attempted what became known as The Vindication Swim, but the bitter conditions forced her to abandon this attempt and she was hauled onto a boat just seven miles from reaching shore. She had slipped in and out of consciousness during this swim and it was her determination to persevere that endeared her to both the public and the Press.

As Miss Gleitze sat exhausted in the boat headed to shore, a journalist noticed that she had a watch dangling around her neck. He asked to have a closer look at it and was amazed to discover that it was water-tight and still keeping accurate time.

The rest is history. It was a brilliant stroke of marketing on the part of Rolex founder, Hans Wilsdorf, and it helped cement Rolex's reputation for water-proof watches.

Just over a decade later, an Italian manufacturer, named Panerai, began supplying the Royal Italian Navy with wristwatches. These watches had cases and movements made by Rolex and later became part of the equipment used by Navy divers during the Second World War. This is a Radiomir model from around 1940;

 Picture from https://www.watchtime.com | Vintage Eye for the Modern Guy, Part 9: Panerai Radiomir

 

And, even in this heavily-used vintage state, you can see that it demonstrates the most important aspect of a dive watch- legibility. Okay, forget that the Radium coated numerals on the dial have faded over the years (actually, it appears there may have been some water-entry into the case at some point). This watch is very interesting for the fact that the dial was made up of two separate sections. The main dial had the hour markers and numbers cut out of it, like a stencil. This dial was then placed over the top of another disc that was coated in luminous (and radioactive) Radium compound. The end result provided a highly visible-in-low-light watch dial. The watch above is extremely rare. Panerai's wristwatch manufacture was primarily produced for military use only, from the late 1930s through to the 1950s, before the brand was resurrected in the early '90s and began regular production for civilian use.

But I digress a little.

Okay, so Panerai made this type of watch for military diving puposes. Jacques Cousteau developed the Aqua-lung breathing apparatus towards the mid-1940s. And fast-forward to 1953, where I started this topic, and the sport of scuba-diving was just beginning to get popular. At the Watch & Jewellery Fair in Basel, Switzerland that same year, Rolex unveiled its Submariner model, specifically aimed at those who wanted a watch for both recreational and professional diving. And this watch looked like nothing else...

Picture courtesy of the outstanding www.rolexblog.blogspot.com.au/


...except perhaps the Blancpain Fifty Fathoms, which premiered at the same watch fair the same year;


picture courtesy of http://oceanictime.blogspot.com.au

Now, they don't look exactly alike and they can't be mistaken for one another, but both of these watches have become stone-cold classics, as far as dive watches are concerned. Both are extremely rare and highly collectible, but while few outside of watch-collecting will have heard of the Fifty Fathoms, the Submariner is a well-known watch to many. I'm not sure of Blancpain's production output of the original Fifty Fathoms. I think they were in production for about ten or twelve years (don't quote me) whereas the Rolex Submariner has been in uninterrupted production since 1953. Yes, it has undergone countless major and minor design changes over the years, but it essentially retains its major aspects that have ensured its status among watch enthusiasts for almost sixty years. Oh, and Rolex had an aggressive marketing campaign throughout the '50s, '60s, '70s and '80s. You couldn't pick up an issue of National Geographic, Reader's Digest or TIME Magazine without seeing an ad for a Rolex watch. Those ads have become classic too. Great ads that really emphasised the accuracy of the time-keeping and robust qualities of the brand.

The modern Submariner looked like this up until about two years ago when the design was given a slight tweak. This is the 16610 reference;

Picture courtesy of www.thewatchclub.com

        Which has been replaced by the 116610LN reference;

Picture courtesy of www.gemnation.com

Still, Blancpain's sales were boosted by Lloyd Bridges as retired U.S. Navy diver Mike Nelson in the early 1960s TV series "Sea Hunt". 

Here he is on the cover of  Skin Diver Magazine wearing a Blancpain Aqua Lung wristwatch, next to a vintage example of the watch itself.

Picture courtesy of claude f. on http://blancpain.watchprosite.com/?show=forumpost&fi=4&pi=3629466&ti=583211

Blancpain has re-introduced the Fifty Fathoms series in the last couple of years. It's a faithful reproduction of the original, except for the new, modern size of 45mm in diameter. 

There are three basic similarities between these two classic watches and, as such, these elements have become the three main British Ministry of Defence requirements for a diver's watch (aside from water-resitance beyond 200-300 metres).

1) Legibility- the hands and hour markers need to be visible in low-light conditions. They have to be visible in complete darkness. Radium and Tritium were used in past decades, but, as mentioned already, these were radioactive. The solution to this arrived sometime in the '90s when SuperLuminova was developed. This compound is safe to use on watch dials, but its luminescence is not as long-lasting as Radium or Tritium. It's still good enough for today's purposes, however, and will easily glow for the duration of a dive, especially if it's been exposed to light beforehand.

2) A Uni-directional Rotating Bezel- this used to be crucial in the days before dive computers were developed. I would argue that a dive watch still makes a good back-up in case your dive computer is damaged while underwater or its batteries die. Anyway, most true dive watches have a luminous dot or pip on the twelve o'clock marker of the bezel. The bezels will normally have five-minute markers with a number on each of the ten-minute markers. Immediately before a descent, you would rotate the bezel so that the luminous pip lines up with the minute hand on the dial. Taking the Blancpain above as an example, let's say you have 45 minutes of air in your tanks. You would line up the bezel with the minute hand, so the bezel pip would be in line with 10:10 on the dial. If you have 45 minutes of air, then you'd know that you'd have to be back up on the surface at 10:55. Sure, you could just tell yourself to be back up at 10:55, but this method provides an at-a-glance readout. One less thing to concern yourself with while underwater. The reason why these bezels need to be unidirectional, and more importantly, anti-clockwise unidirectional, is because, if you accidentally graze the bezel against some coral, causing it to turn in its anti-clockwise direction, then it will show that you have less air remaining in your tanks rather than more.

You and I? We would use the bezel for timing down lunch breaks and parking meters.

3) A Running Indicator- basically, a second hand. Something that shows you that the watch is ticking. You don't want to look at your watch while underwater, and then look at it again ten minutes later to find that it's still showing the same time as before. Don't panic. Don't rush. Get to the surface.

So, these three features are the main elements of a dive watch.

By the mid-Sixties, almost every brand was making a dive watch. There were obscure brands like this Orvin.

I bought this one off eBay and was slightly disappointed when it arrived. The case measured around 36mm, which would have been great if it were a dress watch, but I'd gotten used to dive watches being a tad larger, say, around 38 to 40mm. But this watch was from the '60s, so it was the average size for a lot of watches back then.

There are those who have said that ALL dive watches are based on the design of the Rolex Submariner, but I would say that this is a very narrow-minded viewpoint.

Omega brought out a Seamaster Diver's watch in 1957 (a banner year for the brand) and it has since become a classic as well.

Ladies and Gentlemen, the Seamaster 300;

Notice with this watch that Omega have removed as many similarities to the Rolex Sub as they possibly could, while still (obviously) retaining essential dive watch characteristics. The dial uses baton markers instead of dots, the hands are sword-shaped instead of Rolex's classic 'Mercedes' hour hand, and the bezel on the Omega is acrylic instead of Rolex's more practical aluminium. This particular model was in production from 1964 till around 1972 and I have often said that if Omega had kept up production of this model along the same lines as the Submariner, they would have punched a serious dent in Rolex's sales.

Omega released their Planet Ocean series dive watch (below, right) in 2005 and its design borrowed much of the Seamaster 300's DNA;

Notice the use of arrow-shaped hands? This was used on the original Seamaster dive watch from 1957.

There were many notable brands that created diver's watches that, while maintaining the elements that were first introduced by both the Rolex and Blancpain, managed to put their own spin on the dive watch aesthetic. Longines released this watch in 2007;

Picture courtesy of www.forum.tz-uk.com

It's a very faithful reproduction of a watch that Longines first released in 1960. The main difference with this watch and most other dive watches of the time was the internal bezel, which was rotated by the extra crown located at the 2:00 o'clock position on the case. There were other brands that incorporated this type of bezel on their dive watches and many brands have reintroduced this style of dive watch as part of their collections in recent years. Here's the IWC Aquatimer that is part of the company's Heritage Collection.

pic courtesy of http://tyylit.fi/foorumi/viewtopic.php?f=2&t=146

And, of course, let us not forget the Japanese contingent. Brands such as Seiko and Citizen were producing affordable and robust dive watches which sold like crazy throughout the 1970s and '80s.

The Seiko Auto Diver has undergone a few changes since its inception (pic courtesy of www.amazon.com);

The off-set crown (at 4:oo o'clock) and the two-tone bezel of this SKX009K1 model have become signature features of this range. These are automatic watches which possess varying degrees of accuracy, but what they lack in terms of timekeeping, they make up for in terms of ruggedness. You could practically park a car on one of these and they would still run.

Again, we have a watch that can't really be mistaken for a Rolex Submariner.

But then, when Seiko want to make something a little more like a Rolex, then this watch is a nice example. The SKX031;

Not a true diver's watch for one particular reason- the bezel has no luminous compound on it at all. But, for you and I who don't dive (you don't dive, do ya?), this watch is all we need. One hundred metres of water-resistance is more than enough for a day at the beach.

But if you're after a dive watch that will NEVER be mistaken for any other brand, then this one's for you. Humbly known as "The Orange Monster";

Picture from; Two Broke Watch Snobs | A Life on Wrist: Seiko SRP309 Orange Monster

As modern a design as you could hope for. Also available with a black dial. One thing to mention about this dial colour- Orange and yellow are the last two colours that fade in the colour spectrum the deeper you dive, hence the reason why it was a popular choice for dive watches since the early '70s.

Doxa released the classic Sub 750T around forty years ago for professional dive use. Here is a modern limited re-edition (picture by MattV on Watchuseek.com sales forum;

Oh, another thing to point out about some dive watches- There were a few brands that made the minute hand larger to make it more legible against the bezel for actual dive usage. The Doxa on the left clearly shows this, and Omega's classic PloProf model from the early '70s also had this type of minute hand.








In this photo below (courtesy of www.fratellowatches.com) , the original model from back then is on the left, and the current re-edition is on the right;

Notice the use of orange to make this hand stand out. Some dive watches, like these two Omegas, positioned the crown on the left side to better protect against accidental knocks.

So, as you've seen, there's a variety of diver's watches on the market. Plenty to choose from ranging in price from around $120 for a Seiko automatic to about ten grand for an Omega PloProf or a modern Rolex Deep Sea SeaDweller.

Now, onto some other points worth mentioning, based on or inspired by some of the things I noticed during my selling days.

NEW or VINTAGE?

With dive watches, the question of whether to purchase new or vintage will often hinge upon whether or not you actually plan to dive, or even swim, with the watch on. If you’re looking to get yourself a fairly well-worn dive watch from the ‘60s with a view to submerging it in water, I would caution you to think again. Better yet, check with a watchmaker before you purchase. I don’t have any vintage dive watches, but I do have a totally re-built (from spare parts) Omega Seamaster that I got checked out by my watchmaker. He gave it a clean bill of health and said that it was good down to 200m like the original model from the late Sixties. But, there’s no way in hell that I’ll be putting that watch under water.

Most watchmakers I’ve spoken to have told me that they never guarantee the water-resistance on a vintage watch because there are too many variables. Case-backs that have warped over time due to extremes in temperatures or knocks, case-back threading that has worn down due to excessive unscrewing, moisture penetration, etc. 

Another consideration is- how badly do you want a vintage piece? There's a little more care required with a vintage watch. Mostly, it has to do with the fragility of the crystal (the glass) which, until sometime in the late 1980s/early 1990s, was made from Hesalite, acrylic or mineral glass, which was more prone to scratches and breakage if hit too hard. Now me, I'd love to get a Submariner from say, l970 to 1980. I've wanted one since I was an impressionable, young James Bond fan back in the mid-Seventies. Unfortunately, it will cost me as much as a modern, brand new one. But the vintage model exudes so much of what I saw of of the brand through its legendary magazine ads before the Yuppie brigade adopted the brand as part of its uniform, thus ruining what Rolex is all about.

If you are DEAD-SET certain that you'll never put the watch under water, then go ahead and buy a vintage dive watch. I met plenty of customers who told me that they've dived wearing their 30 year-old Seiko/Omega/Rolex/Citizen dive watch, but I more clearly remember the customers who came in with some beautiful dive watch in nicely aged, original condition that has filled up with water because the caseback threading has worn over the years, and even though those watches could be serviced, cleaned out and gotten back to working condition, chances were that many of those nicely aged hands and dials would have had to be replaced with new ones. Sad, but true.

Other than that, what I wrote in my other post about vintage versus new pretty much applies to dive watches as well.

You can’t wear a dive watch with a suit!

Oh yes, you can...within reason. The Patron Saint of Dive Watch with Suit was (and is) none other than James Bond himself. Now, I’m speaking of the cinematic incarnation of 007 rather than the literary one. The watch that Bond wore in Fleming’s books is a whole other can of worms that I won’t go into here. Oh, by the way, did you really think I could do a write-up on dive watches without mentioning James Bond? Probably, but meh, we've come this far, right?

Now, I would be the first to say that Sean Connery’s watch in the pre-credits sequence of “Goldfinger” (Dir: Guy Hamilton, 1964) looked out of place on his wrist.

It looked great when he’s clad in black stealth-gear and laying plastique explosives over barrels of heroin.
However,  a few minutes later when he’s in the cantina wearing a white dinner jacket (I’m not gonna give away the costume change for the half a dozen people in the world who haven’t seen this film)...

 

 
Picture taken from http://rolexblog.blogspot.com.au and Courtesy of EON Productions/DanJac LLC

...and he glances at his watch, it just appears very out of place on his wrist against the suit that he’s wearing (in this screen-cap from the film, taken off James Bond Lifestyle.com/Product/Rolex;

If you look carefully, you’ll see that the watch is ‘under-strapped’. The lugs (those two protruding bars where the strap or bracelet attaches to a watch) on his Rolex Submariner are 20mm wide, whereas the nylon strap that’s fitted to it is 18mm, hence the spring bar is visible. There have been a million different theories and anecdotes as to why this occurred. I read once that the Rolex belonged to one of the crew and, in order to get a proper fit for Connery, somebody was quickly sent out to purchase a cheap strap for the watch so it could be easily adjusted to fit. These straps were readily available from newspaper kiosks on the streets of London back in the Sixties. That story seems to make sense to me and it would explain the incorrect sizing too, since an 18mm strap is what you would find on most men’s watches back then.

I've read of some hard-core Bond fans who put an 18mm True Bond strap on their Rolex Submariners to achieve the exact same look. I think it's silly. And I'm a hard-core Bond fan. Oh yeah, the True Bond strap is like the one way up above on the Omega Seamaster 300. Basically, kids, if the lugs are 20mm wide, put a 20mm wide strap on it. Simple.

I've listened to customers tell me that you can't wear a dive watch with a suit. I've always said to them that if it's good enough for James Bond, then it's good enough for me.

The first week that I started working in the watch industry, a man in his 60s looked at the Omega Seamaster Professional that I had on my wrist...

...and said to me; "That looks ridiculous with a suit."

Funnily enough, I don't remember him buying me the watch. I bought it myself. For myself.
Upon reflection, I probably should have smacked him one in the mouth. Anyway...

I had a few customers who would walk into my store wearing a suit and some old 1970s Seiko dive watch on a crappy Velcro or nylon strap. Nothing, and I mean nothing cheapens a suit faster than a Velcro strap on a watch. My opinion only. If you want to wear a dive watch with a suit, your safest option will be a steel bracelet or perhaps a leather strap. Just don’t let the leather get too trashed. Which brings us to...

BRACELET, STRAP or SYNTHETIC?

A dive watch perhaps offers the most strap variations than any other kind of watch and there are a myriad number of choices on offer.

NATO/ZULU

NATO straps are a personal favourite of mine, for a number of reasons. They're cheap, they're very comfortable (especially in hot weather), and they are very secure. So, to break it down a little, here I go- you can pick these type of straps up off eBay for anywhere between $15-$30.

They're comfortable because they're made from very pliable nylon and if they get dirty, you just throw them into the washing machine with your socks and underwear.

And, most importantly, they're secure because the strap itself does not fasten onto the lugs, but rather, it passes underneath them.

Like so;

And then you're ready to strap it onto your wrist. And if, by chance, one end of the strap comes away from the case, the other end of the strap will still hold the watch to your wrist;





The NATO straps are designed according to Ministry of Defence specifications. The US version is what's known as the ZULU strap. Same concept and design, but with larger oval-shaped steel rings.

STEEL BRACELET

If you never plan to wear your dive watch for actual scuba diving, then the steel bracelet option may be for you. It is usually the most...uh..."butchest" look for the entire watch. With something like my Planet Ocean, I will sometimes swap the bracelet for a leather or rubber strap, but I find myself switching it back to steel. With its standard (and solid) three-link construction,it's the best look for this watch.

Another steel option is mesh. It's basically a woven steel bracelet design that first appeared in the late '60s when scuba diving was hugely popular. It's on the Omega PloProf watches up above somewhere, but if you can't be bothered scrolling up for it, basically, it looks like this;

Very comfortable to wear because it moulds to the curve of your wrist. The weave in the steel allows for excellent air circulation, too. And best of all, you'll look like Burt Reynolds in "Deliverance" (Dir: John Boorman, 1972) with this on. He didn't wear this in the movie, but he should have.

RUBBER/TROPIC

Rubber straps are great for the summer months when your wrist can swell up throughout the day. If your dive watch is on a steel bracelet, this can make for an uncomfortable fit. You then have two options- add an extra link or half-link (if available) to the bracelet, which may cause it to feel too loose when the day cools down, or leave it as is, in which case it may begin to feel uncomfortable as the mercury rises.

A rubber strap is a good option because it will give a little as your wrist swells. Many brands offer an in-house rubber strap that's made for your watch. The Planet Ocean rubber strap is pretty sturdy. I wore it last year while in Thailand and it served me well.

As the temperature rose throughout the day, I adjusted the strap. And, of course, it's water-proof. If worn in salt-water or a chlorinated swimming pool, it's a good idea to rinse it off afterwards in fresh water to extend its life-span.

Tropic straps are cool, too. If your brand doesn't make a rubber strap for your watch, consider one of these. They've got a super-cool (dare I say it? Go on, teeritz!) funky, retro, atomic look to them, since they are based on an old design from the mid 1960s.

Quality-wise, these aren't bad at all. About fifteen bucks, so it's probably worth buying three or four of them. They should last you quite some time.

LEATHER

Leather straps can often make a dive watch a little dressier, depending on the grain of the leather. They can also make the watch look a little more old-school. Which is not a bad thing. I tend to go for a plain black leather with a contrasting white stitching along the edge. Even though this photo doesn't show that kind of strap.

 

Reason I like the white stitch is because it compliments all of the white hour markers and hands on the dial. Naturally, you can't get these leather straps wet. The minute you do, I can pretty much guarantee that the strap will start to smell like an old pair of shoes about a week later. And nobody wants that.

Same thing goes for shark-skin straps. One customer asked me why wasn't a shark-skin strap water-resistant. "It's a shark, for crying out loud", he added.

"No, sir. It was a shark. Last time I looked at it, it wasn't getting a regular supply of blood and oxygen."

CROCODILE/ALLIGATOR

These are the dressiest option of all. Again, if you never plan to submerge the watch in water, then go for a crocodile or alligator strap. I don't actually have any real crocodile/alligator straps on any of my watches. Read my other 'how to buy a wristwatch' post to learn why, 'cos I'm too lazy to repeat it here.

picture courtesy of www.dangerous9straps.com

A crocodile or alligator strap actually doesn't look bad at all. However, since I've had the image of a Rolex Submariner on its original steel bracelet stuck in my subconscious for almost 40 years, it would be hard for me to wear that particular watch on that particular strap. Your methods may vary.

But it looks pretty good, I have to say. Google 'Rolex Submariner on alligator strap' to see a bunch of pics. 

What else is there to mention?

Right, so we are nearing the end of this. Land sakes, this post has gotten much, much longer than I thought it would, but I wanted to include as much as I could think of. There are a few other things to mention specifically about dive watches.

To maintain true water-resistance, a dive watch must have a screw-down crown. Simple as that.

A proper diver's watch also needs to be at least 150m water-resistant. Most recreational divers don't really tend to go deeper than 20 to 40 metres down, so 150 metres should be sufficient. Remember, it's to do with atmospheric pressure on the watch case rather than actual depth.

Some brands incorporate a helium-escape valve somewhere on the case. The modern Omega Seamasters have a manual helium valve located near the ten o'clock side of the case. To use it, you need to manually unscrew it once you've reached the surface.

Here's how it looks in Omega's Instruction Booklet;

Picture courtesy of www.forum.tz-uk.com

Fig. 2.1- Helium valve closed.

Fig. 2.2- Helium valve unscrewed.

Fig. 2.3- Any helium which has built up inside the case* will force its way out through the valve. The little black dots that you see in these drawings are rubber gaskets, designed to keep water out during this helium purging process.

*Helium molecules, as found in the air inside diving bells during extended dive time, can seep into a watch case. Once inside, there's no way for this helium to escape except via the weakest part of a dive watch-the adhesive that holds the crystal to the case. 

Rolex, on the other hand, has a simple, in-built helium valve which requires no help from the wearer, but works on the principle of pressure (from the built-up helium) against an internal spring in the case. And, it was Rolex that first came up with a helium escape valve back in the '60s, when divers would ascend to the surface after a dive and the crystal on their watch would shatter or dislodge from the case. It was first introduced on the famous SeaDweller model and has remained so ever since.

Extension clasps- Many watches made for dive use will have a small hinged section under the clasp that can be unfolded to allow the watch to be worn on the outside of a wetsuit sleeve. Here's how it looks on the Omega Planet Ocean Chronograph;

Picure taken by John Torcasio and featured on his blog; http://omegaplanetoceanchrono.blogspot.com.au/2010/09/omega-seamaster-planet-ocean.html

The section on the left in this picture is the part of the clasp that folds over when you put the watch on. The other section to the right is the folding clasp, which stays tucked under the main clasp until needed.

And here's the extension clasp on a Rolex Oyster bracelet, as used on their Submariner and Seadweller models until a few years ago;

Picture courtesy of http://luxurytyme.com/en/rolex-related-articles/a-tutorial-on-how-to-open-the-rolex-dive-suite-extension/

Rolex have changed the construction of their clasps in recent years and it all works differently to the one above, but the basic principle remains the same-a simple mechanism to extend the length of the bracelet so that it can be worn over a wetsuit.

Luminosity- A dive watch dial should glow in the dark. Exposure to artificial or natural light should be sufficient to give your dive watch dial enough glow to easily last a few hours. Most modern watch dials use SuperLuminova, as far as I know, but there is another substance known as C3. Same stuff. It glows in the dark. There are various colour options too. The hour markers can be painted to glow an off-white, creamy tone, or orange, yellow, blue, green, the list is almost endless.

Picture courtesy of www.bernardwatch.com/blog -Which Watch Is Better? A Submariner or a Seamaster? Late 90s to Early 2000s Edition

Here, you can see the dial of an Omega Seamaster Planet Ocean on the right and the Rolex Seadweller dial on the left.

After reasonable exposure to light, your dive watch dial should be visible in the dark all night long. If you wake up at 4:00am, for example, you should be able to make out the time on your wristwatch. It will look faint, but it will still be legible. Over time, and we're talking years here, this brightness will tend to fade as the chemical composition of this luminous substance begins to break down. This is when you would think about replacing the dial and hands on your watch when it next requires servicing.

Some brands have taken to using one colour for the dial markers and hour hand, and then another colour for the minute hand and bezel pip. This is to further differentiate between those hands if diving in total darkness or during a night dive. The new generation Omega Planet Ocean series uses alternating colours for this purpose;

Picture courtesy of www.prestigetime.com

Notice here that the minute hand and the pip (or dot) on the bezel have a greenish tinge, whereas the hour hand and dial markers glow bluish. For somebody diving at night, this is a useful backup.

Ideally, however, whether it's day or night, there should be no way of misreading the time on a dive watch, since that's primarily what they're designed for.

Size- Ahh, yes. This is where dive watches were the first culprits to begin pushing beyond 40mm in diameter. These days, you can get dive watches in 36mm (although these are now considered to be a 'boy's' or 'lady's' size. However, if you feel comfortable with this size of watch, then go for it) and all the way up to 49mm.

In saying that, Panerai released the Egiziano (The Egyptian) back in the late 1950s for use by the Egyptian Navy. It measured a whopping 60mm in diameter;

Picture courtesy of  www.vintagepanerai.com

That particular model sold at auction through Christies for a...staggering 147,000 Swiss Francs  ($152,000AUD approx) a couple of years ago.

And they brought out a Limited (to 300 pieces world-wide) re-edition a couple of years ago;

Picture courtesy of http://truetimetools.com/2010/09/18/panerai-radiomir-egiziano-pam341/ and SJX and http://www.watchprosite.com/

Definitely not for the faint-hearted. I served a customer early last year who had one of these on his wrist. I had to laugh, but thankfully, he got the joke too. He told me that he thought it was ridiculously large when he first saw it, but he knew that he would never see one of these again and so he decided to buy it. The limited edition aspect of this watch means that it will be collectible and highly sought-after (if it isn't already) in future. He handed me the watch. The strap was wider than the belt around my waist. I laid the watch over my wrist (I didn't dare try it on) and laughed again. This thing was HUGE!!!

Dive watches will often tend to sit high on the wrist because of the extra thickness of the case. Always, I repeat, always, try it on before you make up your mind to purchase or not. But then, I say this of any wristwatch that you may be comtemplating purchasing. Here's the thing that I used to say to customers; "You're gonna look at this thing ten or twelve times a day when you want to know the time, so you may as well like what you're looking at. I want you to choose the watch that, five, ten, twenty years from now, you'll look at and know that you made the right choice."

It's that simple.

In concluding this post, I have to admit that I've got a soft-spot for dive watches. As a desk-diver (watch-nerd terminology for somebody who doesn't scuba dive, but wears dive watches), I find that the clarity of the dials, the more-than-I'll-ever-need water-resistance, and the robustness of these watches holds a certain appeal for me. And if you find yourself with a decent dress style watch, but want something that's a little more sports-oriented and water-friendly, then I personally think a diver's watch is the way to go.

It's not a style of watch that appeals to everybody, but those who like them tend to swear by them. Regardless of the brand.

And that is that. I keep thinking that I've neglected something, but I've spent the better part of the last ten days writing (and rewriting) this post and I think I've covered all the bases. Certainly, there'll be those of you out there who will disagree with me or find discrepancies in what I've written. That's  what the rest of the internet is for. To cross-reference against what I've written.

And remember, you CAN wear a dive watch with a suit. And a double-Scotch.

Thanks for reading, all!

P.S. - to the owners of any photos that I've used here, thank-you very much! If you'd prefer that I remove them, let me know.