An ongoing series casting a spotlight on A. Lange & Söhne's chronograph timepieces
In the world of mechanical watches, a chronograph remains one of the most desired complications. Its history began in the 18th century, used as a "tool" to measure time in the fields of military, science and sport.
To this day, hundreds of years later, the chronograph retains its allure and charm. It also remains one of the greatest challenges in precision watchmaking to build and design a chronograph calibre. Only a few manufacturers at this moment in time have the ability and knowledge to develop a craft such a mechanism. A. Lange & Söhne is one of this rare breed.
With a total of 13 manufacture movements - movements made in-house - A. Lange & Söhne has always had pride in place for its chronographs, which are in turn highly coveted by owners since 1999. A. Lange & Söhne's chronographs are based on the column wheel principle, with column wheels that control basic functions: start, stop and reset. Depending on the oscillator, events can be measured with an accuracy of one-fifth or one-sixth of a second and, thanks to the minute counter, can last as long as 30 to 60 minutes.
With this level of precision in timekeeping, the Saxon Manufacture is truly in the halo-ed company.
By Kien Lee
Joining the family of DATOGRAPH models, the DATOGRAPH UP/DOWN "Lumen" is the chronograph that never sleeps.
Deployed with a "Lumen" execution, the fourth model in the A. Lange & Söhne's "Lumen" series, a new aesthetic dimension reveals itself as soon as darkness sets in. This is possible through the deployment of a semi-transparent dial and a luminous compound that causes all displays to flow in the darkness with a distinctive green hue.
The hour and minute hands are filled with the same luminous material, along with the chronograph sweep seconds hands. The seconds hand and minute counter in blued steel revolve above subsidiary dials that are noctilucent. The circumferential dial ring with the minute scale that is subdivided into fifth-of-a-second graduations, the concentric tachometer scale and the power-reserve arrow applique also glow in green.
Finally, the iconic outsize date is luminous as well. Composed of two separate display elements, the outsize date is designed to glow immediately after the midnight switching sequence as well. This is made possible with a luminous tens cross and a black printed units disc made of transparent glass which rotates above a luminous background. Both elements recharge during the day when they are positioned beneath the dial - possible because of the aforementioned semi-transparent dial.
The DATOGRAPH UP/DOWN "Lumen" is equipped with the manufacture chronograph with flyback function, allowing consecutive measurements - an ongoing measurement can be interrupted and a new one started instantaneously with a single touch of a button at 4 o'clock.
This rare function saves time because the flyback mechanism executes the three normally necessary stop, reset and restart steps with only one touch of a button.
The precisely jumping minute counter of the chronograph advances by one marker exactly when the chronograph sweep-seconds hand passes the 60th second, even if the time measurement is stopped at that very moment. This elaborate technology simplifies the doubt-free reading of stopped times.
Launched in 2012 as a systematic refinement of the classic column-wheel chronograph, the DATOGRAPH UP/DOWN also indicates how much of the 60-hour power reserve remains available. This information is provided by the power-reserve indicator at 6 o’clock. When the small arrow enters the red zone of the display, it is time to provide the movement with fresh energy.
Utilizing Lange’s proprietary cam-poised balance wheel, paired with a freely oscillating Lange hairspring, the DATOGRAPH UP/DOWN "Lumen" beats at a frequency of 18,000 semi-oscillations per hour (2.5 hertz). In combination with the 300-marker minute scale, this allows the watch to make time measurements with a resolution of one-fifth of a second.
The DATOGRAPH UP/DOWN "Lumen" is available in a limited edition of just 200 watches, and comes in a 41 mm platinum case. It is worn on a black alligator leather strap with a platinum prong buckle.
