The Excalibur Bi-Retrograde Calendar by Roger Dubuis

This year, Roger Dubuis celebrates its 30th anniversary, and for the occasion, the company pays tribute to its co-founder’s favourite complication: the bi-retrograde display.

This function, previously featured in the Excalibur Grande Complication alongside a dozen other highly complex mechanisms, takes centre stage once again. The Maison has also introduced a less complicated, more classic edition to further honour the bi-retrograde display.

Also referred to as “the ecliptic counters” by the Maison a nod to their elliptical shape and distinctive role in indicating the months and date the design showcases a symmetrical dial layout. Enhanced by refined detailing, it pays homage to the Maison’s early creations from 1996.

Glossary

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Glossary
Gnomon

Gnomon

Is a device used in timekeeping and astronomy to determine the position of the sun and track the passage of time. It consists of a vertical rod or plate that casts a shadow onto a surface, typically a dial or scale. The length and orientation of the shadow change throughout the day as the sun moves across the sky. By observing the position and length of the shadow, one can determine the time of day, the direction of the sun, and even the time of year. Gnomons have been used since ancient times and are still employed in sundials and some modern instruments for measuring solar angles. They provide a practical and visual way to understand the movement of the sun and keep track of time.