The world time function is also very easy to use. The hour and minute hands indicate the time in the city and time zone whose name is shown at 12 o’clock. The time in the 23 other zones can be quickly and easily determined with the city disk and the two-colored 24-hour ring which instantly tells the user whether it is day or night in the respective city and time zone. When traveling from a time zone to the next, pressing the corrector button at 10 o’clock advances the city disk and the 24-hour ring counterclockwise in one-hour steps as well as the hour hand clockwise, also in one-hour steps. The correction is finished when the city name of the destination time zone is at 12 o’clock. During this process, the world time mechanism and the hour hand are uncoupled from the movement, so neither the amplitude of the balance nor the steady progression of the minute hand are affected.
The CH 28-520 HU automatic movement has a CH 28-520 PS chronograph caliber with column-wheel control and a vertical clutch, as well as a world time module. The chronograph has a start/stop pusher at 2 o’clock and a reset pusher at 4 o’clock that also doubles as a flyback pusher. When it is pressed while the chronograph is running, the sweep hand flies back to zero and a new time measurement is started automatically. Because the chronograph hand is powered via a vertical clutch, it can also be used as a permanently running seconds hand without risking undue wear and without affecting the rate accuracy and power reserve of the watch.
The ref. 5930 comes in a white-gold case with a blue, hand-guilloche dial center. The strap is a matt navy blue alligator strap with large square scales to match the dial, and an 18K white-gold Calatrava fold-over clasp. The retail price is $73,700. The other noteworthy release, and a future classic, is the 22nd iteration of the annual calendar, Ref. 5396. The in-line double aperture in the upper half of the dial displays the day of the week on the left and the month on the right. The date display is positioned in a large aperture at 6 o’clock. The 24-hour subsidiary dial with the moon-phase display is positioned above the date aperture. This layout is reminiscent of Patek’s perpetual calendars from the 1940s and 1950s.
The retail price is $73,700