question: Why do high end luxury watches such as Rolex have such a strong connection to diving?
comment: Prior to dive computers being reliable and accessibly priced having a very reliable timekeeping device was a must-have for diving. It's important to time dives out properly to avoid problems like decompression sickness.
passages: In 1961, Edox launched the "Delfin" line of watches, with industry-first double case backs for water resistance to 200 meters. They later released the "Hydrosub" line in 1963 featuring the first crown system with tension ring allowing depths of 500 meters.
  
  In 1961, Rolex began to include a skindiver handbook with the Submariner, then available in two models, one water resistant to , the other, less expensive version, to . It was the choice of watch for the character of 007 in the first ten James Bond films, causing the "Sub" to achieve an iconic status.
   Jacques Piccard and Don Walsh had a specially designed experimental Rolex Oyster Perpetual Deep-Sea Special strapped to the outside of their bathyscaphe during the 1960 Challenger Deep / Mariana Trench dive to a world-record depth of . When James Cameron conducted a similar dive in 2012, a specially designed and manufactured Rolex Oyster Perpetual Sea-Dweller Deep Sea Challenge watch was being "worn" by his submarine's robotic arm.
   Rolex Submariner
  
  The Rolex Oyster Perpetual Submariner is a line of sports watches designed for diving manufactured by Rolex, known for their resistance to water and corrosion. The first Submariner was introduced to the public in 1954 at the Basel Watch Fair. The Rolex Submariner is considered "a classic among wristwatches", manufactured by one of the most widely recognized luxury brands in the world. Due to its popularity there are many homage watches by well-established watchmakers as well as illegal counterfeits. The Rolex Submariner is part of Rolex's Oyster Perpetual line.
   The Rolex Submariner was introduced at the Basel Watch Fair in 1954 which coincided with the development of self-contained underwater breathing apparatus, known as scuba. In 1959, the United States Navy Experimental Diving Unit evaluated five diving watches that included the Bulova US Navy Submersible Wrist Watch, Enicar Sherpa Diver 600, Enicar Seapearl 600, Blancpain Fifty Fathoms, and the Rolex Oyster Perpetual.
   Watch crystals can also be applied as display backs to view the watch movement, but these are a rare feature on diving watches.
  
  Section::::Characteristics.:Crown.
   In 1965, Seiko put the 62MAS on the market, the first Japanese professional diver watch.
  
  During the 1960s, commercial work in the oceans and seas created professional diving organisations that needed more robust watches designed for diving operations at greater depths. This led to the development of the first 'ultra water resistant' watches like the Rolex Sea-Dweller 2000 (2000 ft = 610 m), that became available in 1967, and was produced in several variations, and the Omega Seamaster Professional 600m/2000 ft, also known as the "Omega PloProf" (Plongeur Professionnel), that became available in 1970, and was produced in several variations.
   For easy legibility most diving watches have high contrasting, non-cluttered dials and markers with a large, easily identifiable minute hand. The markers for 3, 6, 9 and (especially) 12 o'clock on the watch face and the zero marker on the bezel of analogue diver's watches are usually conspicuously styled to prevent disorientation induced read out errors. A styling of the hands where no hand can temporarily totally overlay and hence obscure the position of another hand is also desirable to promote constant legibility and prevent read out errors.
   In late March 2012, Rolex announced that a new prototype diving watch was developed and is part of the Rolex supported attempt to dive the DSV "Deepsea Challenger" to the bottom of the Challenger Deep, the deepest surveyed point in the oceans.
  
  On 26 March 2012 the DSV "Deepsea Challenger" carried a Rolex Oyster Perpetual Date Sea-Dweller DEEPSEA CHALLENGE prototype diving watch strapped to its manipulator arm to a depth of of seawater (msw).
   Many companies offer highly functional diving watches. Whilst diving watches are primarily tool watches, some companies offer models that can in addition to this be regarded by some as jewellery or fine mechanical devices. Diving watches can be analog or digital. Besides pure analog and digital models some diving watch models combine digital and analog elements.
  
  Section::::Characteristics.:ISO 6425 standard for diving watches.
   The design and actual availability of diving watches certified for more than is not solely explicable by practical diving needs.
  
  The diving depth record for actual offshore diving was achieved in 1988 by a team of professional divers of the Comex S.A. industrial deep-sea diving company performing pipeline connection exercises at a depth of of seawater (msw) in the Mediterranean Sea. They wore Rolex Sea-Dwellers.
   In 1950, von Büren S.A./Montres began to produce their own range of professional diving watches under the Squale brand name. These watches were not marketed for jewelry shops but rather specialty dive stores.
   Most Sea-Dweller watches incorporate a helium escape valve for saturation diving. Early Sea-Dwellers, however, did not always have the valve. Until the 2017 introduction of the reference number 126600, Sea-Dweller's were also distinguished by the absence of the date magnifier ("cyclops") present on most other Rolex models as it was impossible to attach a cyclops with Ultraviolet (UV) light curing adhesive at the top of a watch crystal exposed to the pressure encountered at its test depth. The Sea-Dweller diving watch range has been standard issue for Comex divers since 1977.
   Omega Seamaster Planet Ocean
  
  The Omega Seamaster Planet Ocean is an automatic professional Swiss made luxury diving watch designed and manufactured by Omega SA since 2005.
  
  It belongs to the Seamaster line and has been characterized, since the beginning of its production, by a 600m/2000ft water resistance, a helium release valve, and the chronometer certification.
  
  Throughout its history, many authoritative international sources have often mentioned it as one of the greatest dive watches of all time.
  
  Section::::History and versions.
  
  Section::::History and versions.:Year 2005: the first version.
   The first variant of Sea-Dweller Deepsea reference 116660 has a classic black dial with white text on the dial.br
  
  A second ""D-Blue""-variant was released in 2014 in honor of James Cameron and his journey to the deepest area of the ocean in the year 2012. It has a blue/black dial and green colored "DEEPSEA"-label.br
  
  A new Deepsea model reference 126660 was introduced at Baselworld 2018. It is equipped with the calibre 3235, a broader bracelet and resized folding clasp and a slightly redesigned case.br
  
  Section::::Diving records.
   The Deepsea model comes in a 44 mm case in steel and is equipped with the brand's patented Ringlock system, which was designed to provide a higher degree of pressure resistance. 
  
  Section::::History.
  
  During the 1960s, the needs of professional divers working at great depths led to the development of the first 'ultra water resistant' tool watches designed for conducting safe diving operations at 300 m (1,000 ft) depths.
   The design and actual availability of divers' watches certified for more than is not explicable solely by practical diving needs.
   Following a request made by the Royal Italian Navy, in September 1935, for a luminous underwater watch for divers, Panerai offered "Radiomir" underwater timepieces in 1936. These watches were made by Rolex for Panerai.
  
  In addition, a large number of "canteen" style dive watches by Hamilton, Elgin or Waltham were made to military specification during and after World War II. However, these watches were made in small numbers, and were not intended for large-scale commercial distribution. Today, interest in these watches is limited to collectors.
   BULLET::::- Case made from solid block of 904L stainless steel, a corrosion-resistant alloy, or gold. The golds (white or yellow) are made in Rolex's own foundry.
  
  BULLET::::- Unidirectional bezel that enables a diver to memorize and follow immersion time. As the bezel only rotates counterclockwise, the dive time can only become "shorter" in case of accidental bezel movement, averting the danger of spending too much time underwater.
   Some diving watch models feature a lockable bezel to minimize the chance of unintentional bezel operation under water.
  
  The exclusive use of a rotating bezel is considered a rudimentary diving technique in the 21st century, suitable for basic, shallow single gas (air) diving only. Non-basic diving profiles and depths past require other more advanced timing and measuring methods to establish suitable decompression profiles to avoid decompression sickness.
   Section::::Characteristics.:Elapsed time controller.:GMT dive watches.
  
  There are some analog dive watches available with a GMT complication. GMT watches were designed for long-haul aircrew and other users who want to track time in different time zones. These watches have an additional GMT watch hand and in the case of diving watches can have a rotating bezel with 24-hours markings instead of minute markings used for reading of elapsed time. With the help of the GMT hand and a correctly adjusted 24-hours bezel the time in two different time zones can be easily read without having to perform arithmetic.
  
  Section::::Characteristics.:Crystal.
   The cases of diving watches have to be constructed more stoutly than typical dress watches, because of the requirements necessary to withstand a seawater environment at depth. As a consequence diving watches are relatively heavy and large compared to dress watches made out of similar materials. Under water sheer weight is of less consequence than buoyancy, which a diver can address by a buoyancy compensator ("BC") vest. Before the introduction of other case materials diving watch cases were made of stainless steel. Stainless steel is however still often used as case material in contemporary diving watches.
  
  Section::::Characteristics.:Elapsed time controller.
   Section::::Characteristics.:Watchstrap/bracelet.
  
  Watchstraps or bracelets for diving watches are generally made of materials that are adequately water (pressure) resistant and able to endure the galvanic corrosiveness of seawater. In practical terms most diving watches feature a rubber, silicone rubber, polyurethane or fabric watchstrap or a stainless steel or titanium metal link or mesh bracelet of adequate length to facilitate wearing the watch over a diving suit sleeve.
   BULLET::::- In 1926, produced a waterproof wristwatch, Rolex Oyster. But it was far from the first company to do (see, for example, the "Submarine Watch" from the First World War, which was made by Tavannes and retailed by Brook & Son in Edinburgh). Wilsdorf even had a specially made Rolex watch (the watch was called the "DeepSea") attached to the side of "Trieste", which went to the bottom of the Mariana Trench. The watch survived and tested as having kept perfect time during its descent and ascent. This was confirmed by a telegram sent to Rolex the following day saying "Am happy to confirm that even at 11,000 metres your watch is as precise as on the surface. Best regards, Jacques Piccard".
   Section::::Notable models.:Sports collections.
  
  Rolex produced specific models suitable for the extremes of deep-sea diving, caving, mountain climbing, polar exploration, and aviation. Early sports models included the Rolex Submariner (1953) and the Rolex Sea Dweller. The latter watch has a helium release valve, co-invented with Swiss watchmaker Doxa, to release helium gas build-up during decompression.
   In 1954 Rolex launched their first specialized diving watch known as "The Rolex Submariner." Rolex worked with legendary French explorer and aquanaut Jacques-Yves Cousteau to test early prototype Rolex Submariner watches. The Submariner became commercially available after it was introduced at the Basel Fair Show in 1954.
  
  Section::::1954: The Rolex GMT-Master.
  