Daniel Roth Perpetual Calendar Time Equation

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The quest for the expression of true time has always fired the imagination of master watchmakers, while the combination of horological complications competes with the most advanced technologies. With this fascinating new model, the Masters Grandes Complications collections offers an open window on spheres of celestial accuracy.

Whereas mathematicians and astronomers have striven from ancient times to the present day to determine the equation of time with amazing accuracy by means of ultra-complex calculations, devotees of Daniel Roth wristwatches can now evaluate the difference between mean solar time and true solar time whenever they wish at a mere glance.

First presented in 2004, made entirely in-house and based on a self-winding movement, this model has been entirely updated in 2007 to reflect the classic and contemporary lines of the Daniel Roth collections. This model features a perpetual calendar with the moon phase at 6 o’clock. There are two opposite indicators: between 10 and 11 o’clock, an indicator showing the difference between actual time and the time calculated by means of the time equation; and between 1 and 2 o’clock, an indicator of the number of days of the month in progress, based on an operating system patented by Daniel Roth.
Introduced in 2007, the Perpetual Calendar Equation of Time offers five complications enriching the same movement and naturally finds its place in the Daniel Roth prestige collection of Masters Grandes Complications. The offset hour and minute indication is accompanied by a perpetual calendar and displays of the leap years, the moon phases, the equation of time and number of days of the month. All these complications are driven by a self-winding movement with a 44-hour power reserve.

In 2004, when this model was first presented, the Daniel Roth master-watchmakers already proved that they were undaunted by any technical challenge or combination of complications. In 2007, this Haute Horlogerie timepiece once again projects an image that is at once classical and contemporary, entirely in harmony with the new Daniel Roth aesthetics imbued with technical complexity and sophisticated elegance.

The 18-carat gold dial base with its spiral guilloché motif features three overlapping brush-finished counters, also in 18-carat gold; a minute circle with snailed finish; as well as a partial hour indication on a white mother-of-pearl plate showing the elongated Roman hour numerals between 10 and 2 o’clock. The first segment, located between 10 and 11 o’clock, shows the owner of this watch the difference between mean solar time and true solar time.

This complex mechanism calculates and represents solar time throughout the year, with a difference that reaches its extremes on February 11th (approximately +14 minutes) and November 4th (approximately -16 minutes). Another segment between 1 and 2 o’clock indicates the number of days of the month. The brand has filed a technical patent for this distinctive and highly legible indication.

The perpetual calendar itself is composed of a day of the week aperture at 9 o’clock, a month aperture at 3 o’clock and a leap-year and date display on a double counter at 6 o’clock. The 18-carat dial features open worked central parts providing a see-through vision of the movement, highlighted by the day of the week and month discs. Crafted in translucent sapphire crystal, the latter accentuate the technical effect of the model while maintaining optimal visibility of the movement.

Finally, a realistic representation of the moon phases, appearing in a window at 12 o’clock, sets the finishing touch to this precision instrument framed by a precious curvex shaped double-ellipse case in white gold, pink gold or platinum and fitted with a sapphire crystal case-back.Like the greatest watchmakers, Haute Horlogerie at Daniel Roth transforms a functional object into an objet d’art that measures time and reveals it in its finest attire.

Stemming from the Masters Grandes Complication collection, the Perpetual Calendar Equation of Time is based on a self-winding Manufacture-made movement entirely decorated with high-end finishing including Côtes de Genève and featuring the following complications: Perpetual Calendar, Moon Phases, Leap-year indication, Equation of Time, and the Day of the month number.

This movement is housed within a signature double-ellipse Daniel Roth case in 18-carat white gold measuring 44 x 41 mm, fitted with a sapphire crystal glareproofed on its upper face and an open back glareproofed on its lower face, along with date correctors at 2, 4, 8 and 10 o’clock. The multi-layer dial in 18-carat gold and mother-of-pearl features several dedicated apertures, while translucent sapphire crystal day of the week and month discs provide a see-through view of the movement. The hand-sewn black alligator leather strap is fastened by a white gold folding clasp bearing the brand logo. Water-resistant to 3 ATM.

Technical details
Movement
Calibre number: DR 114
Power Reserve: 44 hours
Functions: Perpetual calendar, time equation and indicator of end of month
Height: 2.98 mm
Mechanism : 3.00
Diameter: 26.50 x 29.50
Rotor: Solid 18K gold and platinum rotor, in a guilloché pattern
Frequency:28’800 A/h.
Balance: 3-arms Cuproberyllium ring
Balance-spring: Flat
Escapement: Lever
Jewelling: 27 jewels.
Special finishing on movement: Hand-bevelled, Côtes de Genève finishing
Exclusive and patented Daniel Roth movement

Case
White, pink gold 4N18 or platinum, open back with sapphire crystal
Height: 41.00mm
Width: 44.00mm
Thickness: 13.00mm
Distance between lugs: 21.00mm.
Water-resistant: 3atm

Dial
Solid 18K gold, in a guilloché pattern and MOP

Setting
Bezel 2 rows 158 diamonds – 1.42K TW VS to VVS

Wristband
Alligator