Tonda Quator Retrograde Annual Calendar
Photography and text by Peter Chong for Parmigiani
First introduced by Patek Philippe in their 5035, it was initially seen as a cop out...instead of doing a full fledged perpetual calendar, it was easier to make it technically less demanding and make an annual calendar. The Annual Calendar is accurate in showing the day of the month for an entire year, adjusting itself without the wearer's intervention to transition from 31st to 1st of the following month for month endings of Jan/Mar/May/Jul/Aug/Oct/Dec. And from 30th to 1st of the following month for the remainder of the year except for February, where it will need the user to advance the date from either 28th to the 1st of March. In comparison to a Perpetual Calendar, where the calendar automatically adjusts to account for the end of month advance for February, needing a user intervention only once every 122 years.
But since the introduction, the Annual Calendar is seen by more and more as a practical, and less expensive way to have some of the conveniences of a daily wearing watch which shows the day, date, month accurately. One only has to deal with the need to make the adjustment once year.
Enter the Parmigiani Tonda Annual Calendar
Parmigiani's Annual Calendar is a variant of their tested automatic caliber PF332 by adding an annual calendar module, making a new caliber PF339. The calendar showing the date is displayed as a retrograde style – moving from 1 to 31 (or 30 or 29) of each month from day to day, and jumping back to 1 at the end of each month. In addition to this complication, PF339 also carries a moonphase indication which simultaneously show the moonphases in both north and south hemispheres. The moonphase accuracy is the typical 1 day variation over every 122 years.
The dial is nicely laid out, with legible markings for all indications. Poor legibility is frequently a failing of watches which display a full calendar. But Parmigiani manages to avoid this. The date is indicated by a hand with a red marker at its end. This hand traveses a fan shaped arc across the top half of the dial. Very clear. There are additional subdials to show the day of the week and the month. Another subdial show the monphases. A central sweep second hand completes the ensemble.
The movement is designed in-house and fully manufactured by Parmigiani. The design and finish are top grade, and very beautiful. The bridges are polished, and finished to a very high degree in line with the high end horological aspirations of the watch. Each anglage and dicoverture is well polished and performed. The fauss cotes are nicely done, with clear, clean lines. The large centrally mounted rotor is beautifully decorated by a rose engine. As it turns to wind the watch, the edges of the guilloche catch the light, and produces a beautiful glint.
The 40mm case, only 11.2mm thick is nicely finished, and sits comfortably well on most wrists.