Sky-Dweller is an unusual watch, now available in Rolesor, the name that Rolex give to the use of gold and steel together in the same watch. In this piece, the bezel, crown, and centre bracelet links are made in yellow gold. Other parts are in 904L steel. In another version, the combination is between white gold and steel. Sky-Dweller has been on the market since 2012.
Second 24-hour time zone and annual calendar
The thing that sets this watch apart is not Rolesor, but the complication. The GMT function is shown by a rotating disc, while the annual calendar is displayed with the month displayed in windows corresponding to the hour indices. Settings are all made from the crown, with functions selected by rotating the bezel – the brand call it the Rolex Ring Command system. It’s surprising to discover that this GMT watch with annual calendar is one of the most complex watch movements made by Rolex. Calibre 9001 is self-winding and comprises seven patents – another seven are hidden elsewhere in the watch, things like the Twinlock crown waterproofing. It provides 72 hours power reserve, and it is certified as a Superlative Chronometer, Rolex’s in-house procedure that follows after COSC certification and attests to a precision of -2/+2 seconds per day max deviation.
The other striking feature of the Sky-Dweller is the subtlety of the display and its adjustment. Months are not labelled, you just have to remember that the months follow the same numbering as the hours, so December is at 12 o’clock, January at one and so forth. There is a sort of logic behind this: you don’t really need the months on a watch because it’s something you know, you need the date, and on this watch the months display is useful above all for when you are setting up the annual calendar. After it’s been set you’ll only have to adjust the date every 1 March. Also subtle is the rotating bezel, which has three positions, but again they are not labelled, there is no reference mark. You have to get used to using the three positions, with home time adjustment in the fully counter-clockwise position, local time adjustment in the intermediate position, then date, and finally neutral in the fully clockwise position.
The Sky-Dweller has a 42 mm case with screw-down caseback and crown that help make the watch waterproof to 100 metres depth. The Chromalight on the hands and hour indices provides a blue-glowing luminescence. The bracelet’s patented Easylink comfort extension link allows you to adjust the length of the bracelet by 5 mm, without using tools. The yellow Rolesor version shown here has a bracelet combining steel and yellow gold: the white Rolesor version has a bracelet in just steel. It has a folding Oysterclasp.
Hour-hand adjustment for changing time zones
Local time is shown by the central hour, minutes and seconds hands, and the date follows local time, changing instantaneously at midnight. Local hour time can be adjusted independently in one-hour increments both forwards and backwards. This doesn’t affect the minute and seconds hands, and so it is useful when you are changing time zones – or between summer and winter time – without losing precision. The 24-hour home time disc obviously combines the time with day/night indications.
Saros annual calendar system
Rolex have a name for the annual calendar system on this watch: Saros. Come to think of it, Rolex have a name for just about everything: Oyster, Chromalight, Parachrom, Rolesor, Easylink, Twinlock, Oysterclasp… Saros is based on a planetary mechanism analogous to the way in which the sun, earth and moon move and produce recurrent eclipses. The irregular recurrence of 30 and 31-day months is duplicated by four additional gear wheels.
Setting up the Sky-Dweller
The Ring Command bezel has three positions, for setting date, local time or home time, which are actually set using the crown. This part of the movement has 60 components. The watch has to be set in a specific sequence, starting with the home time. You unscrew the crown and pull it out to the first notch, put the bezel into the fully counter-clockwise position, and then you set the home time hour on the 24-hour disc, and the home time minutes. Then you set the local time, shown by the jumping hour hand, by rotating the bezel to an intermediate position and pulling out the crown to the second notch. Lastly you set the date and month, with the bezel turned clockwise to the next position, and the crown pulled out to the second notch. Rotating the crown cycles through all dates and all months so I guess that it could take quite a lot of turning. Then you put the bezel into the neutral position by turning it clockwise as far as it will go.
Price of the Sky-Dweller in Rolesor
Reference 326933 is in steel and yellow gold, and it costs €15,900. Reference 326934 (below) is in steel and white gold, and it costs €13,350. Read more on the Rolex website.