New men and women watches meant for heavy sport use as well as three dyed-in-the-wool diver's watches, have been added to the Zeitmeister collection this year. All of them are certified chronometers from Glashütte.
Pioneers like Hans Hass or Jacques-Yves Cousteau contributed to the popularity of diving in the 1950s, and a new genre of wristwatch was created soon thereafter. The salient features included a high degree of pressure resistance, and thus extreme water resistance. Powerful forces are exerted on a diver under water and naturally also on his or her wristwatch. Already at a depth of ten meters, the ambient pressure is two bar, compared to a pressure of one bar at the surface. Another bar of pressure is added with each additional ten meters of depth.
Before the invention of modern diving computers (which relieve sport divers of a great deal of computational work), a precise timekeeper, a bathometer and special diving tables were essential when planning a dive. The higher pressure conditions below the surface pose a potential risk to divers. Depending on the depth to which a diver descends, narrow temporal limits define the interval that can be safely spent underwater. If a diver wants to return uninjured from the briny deep, maximal ascent speeds may not be exceeded and so-called decompression stops must be made.
Today a proper diver's watch is absolutely obligatory as a second safety system independent of the diving computer. Corresponding to the strict DIN 8306 standard (or its international counterpart ISO 6425), a diver's watch must undergo water resistance and temperature tests and survive them undamaged. Among other ordeals:
• The watch must spend two hours at the pressure prevailing at a depth of 100 meters, then three hours at a depth of three meters.
• It must withstand a pressure 25 percent above the specified maximal pressure resistance.
• It must show no traces of corrosion after being submerged in warm saltwater for 24 hours.
• It must survive alternating immersions in water at 40° and 5° C and afterwards pass the condensation test.
• Its dial must be uncommonly legible.
• The watch must have a rotating ring that can be turned in only one direction (counterclockwise). When the dive begins, this ring must be rotated so the reference mark corresponds to the minute hand. The dive time can thus be read unambiguously and independently of the time of day. Unidirectional rotation is also essential so that if the ring's position should be inadvertently shifted, it will always display what appears to be a longer interval underwater and never a shorter interval.
In the course of their research, the engineers and designers at the Wempe Museum discovered two early diver's watches from the 1960s: the Zeitmeister SkinDiver and the Zeitmeister Swimproof. They were not as big, were less pressure resistant because of the gasket technology used at the time, and they were equipped with bidirectionally rotating bezels to preset the dive time.
Those models proved Wempe's affinity for water. The new diver's watches safety precautions are comprehensive:
• Screw-down case back
• Screw-in crown with large protectors on either side
• Sapphire crystal with antireflective treatment on both sides to ensure optimal legibility
• Luminous hands and markers
• Second hand with luminous triangle
• Readily grasped, unidirectionally rotating, ceramic bezel with notches at single-minute intervals to preset the dive time
• Luminous marking on the dive-time ring
• Five-part, high-quality, integrated, stainless steel bracelets with quick-extension mechanism to lengthen it so that it can be worn over the sleeve of a wetsuit. The folding clasp is additionally protected by a safety catch.
The case, in stainless steel, measures 44m. It has an AR-coated sapphire crystal and it is water resistant to 100 meters.
Movement is the Swiss automatic ETA caliber Valjoux 7753 with 27 jewels, 28,800 vph and a power reserve of 46 hours. It is modified in Glashütte with Wempe's own fine-adjustment mechanism and it is officially certified as a German chronometer according to DIN standard 8319. The caseback is adorned with an engraved relief depicting the Glashütte Observatory, where all Zeitmeister models undergo strict tests.
Dials can be had in silver or black with steel markers coated with Super-LumiNova. The hands are "gun" hands for the silver dial coated with Super-LumiNova and steel hands for the black dial coated with Super-LumiNova. It comes on a steel bracelet with 22mm lugs.
MSRP is $4,255. It is available as of August 2013 at all Wempe locations worldwide.
The case, in stainless steel, measures 42mm. It has a ceramic bezel in black or blue. The crystal is an AR-coated sapphire and it is water resistant to 300 meters.
Movement is the Swiss automatic Sellita caliber SW300 with 25 jewels, 28,800 vph and a power reserve of 42 hours. It is modified in Glashütte with Wempe's own fine-adjustment mechanism and it is officially certified as a German chronometer according to DIN standard 8319. The caseback is adorned with an engraved relief depicting the Glashütte Observatory, where all Zeitmeister models undergo strict tests.
Dials can be had in black or blue with steel markers coated with Super-LumiNova. The hands are steel and are coated with Super-LumiNova. It comes on a steel bracelet with folding clasp, safety catch and extension element with 20mm lugs.
MSRP is $3,540. It is available as of August 2013 at all Wempe locations worldwide.
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