Ahead of next January’s Salon International de la Haute Horlogerie (SIHH), Germany’s A. Lange & Söhne, an SIHH mainstay, has unveiled the fourth addition to its Lumen series of heavily luminous-treated, transparent-dialed limited editions that began in 2010. The new Datograph Lumen features a flyback chronograph, precisely jumping minutes counter, power reserve indicator, and the emblematic outsize date display ? all highlighted in darkness by the use of a luminous compound that glows a particularly pleasant and vibrant lime green.
The A. Lange & Söhne Datograph Lumen Up/Down features bright green luminous highlights on a semi-transparent dial.
The Datograph Lumen, which will be limited to just 200 pieces, has a platinum case measuring 41 mm in diameter. The sapphire dial has a special translucent coating that filters out most visible light except for the UV rays that serve to charge the luminous pigments on the various dial elements with energy. Thus, the darker the watch’s surroundings, the brighter its essential details glow against their background. The watch’s outsize date can be quickly adjusted with a pusher at 10 o’clock.
The rhodiumed hour and minute hands are filled with the light-activated pigment, and the central chronograph sweep-seconds hand is entirely covered with it. The off-centered subdials, one for running seconds, the other for tallying chronograph minutes, are coated with the substance and feature blued steel han...