Creating annual calendar and perpetual calendars is a special challenge, because there is so much information to place on a dial: day, date, month, and in the case of the perpetual calendar, leap year indicator, and there is often a power reserve and a moonphase indicator. These watches demonstrate completely new ways of presenting this information, such as the Cartier Astrocalendaire, or unique arrangements that play with traditional displays, such as the Baume & Mercier Clifton Retrograde. Combined functions are another trend. Both Lange & Söhne and Jaeger-LeCoultre combine the complication with a tourbillon. The IWC places the complication in the context of a diver’s watch, in a whopping 49mm case – the second-largest wristwatch in IWC’s history, next to the Big Pilot’s Watch of 1940.
Jaeger-LeCoultre Duometre Quantieme Lunaire, with manual-wound Caliber 381, assembled and decorated by hand. Functions include hours, minutes, seconds, jumping stop seconds, date, moonphase and power reserve. It has a dial of grand feu enamel.
Lange & Söhne Lange 1 Tourbillon Perpetual Calendar, now with a pink gold case, with a peripheral month ring, date window, subsidiary seconds, a retrograde day of the week index, a moonphase display, leap year and day/night indicators. The tourbillon is visible from the caseback.
Baume & Mercier Clifton Retrograde Date Automatic in a 43mm steel case, with a retrograde index for the date and the day in a subdial at 9 o’clock. The movement is the self-winding Soprod caliber 9094, with a 40-hour power reserve.
IWC Aquatimer Perpetual Calendar Digital Date-Month, a 49mm diver’s watch with large digital display for date and month, a leap year indicator, stop-watch function with hours, minutes and seconds and flyback function. It is limited to 50 watches.
Cartier Rotonde Astrocalendaire Perpetual Calendar, with a flying tourbillon surrounded by perpetual calendar indications positioned on the bridges of the movement, tiered in concentric levels. The movement, caliber 9459 MC, has only gears – no levers or springs – with a central gear with retractable teeth to drive the indications.