Even after a quarter of a century, the experience of the A. Lange & Söhne Datograph continues to give way to the incredulity of our optical faculty. It arrived like a bolt of lightning in 1999, in a time when chronographs were a third-party affair and largely planar in construction. Here was a manually-wound chronograph that was so complete from a traditional, technical standpoint, incorporating an instantaneous jumping minutes, a flyback function and a clutch lever that pivots concentrically with the axis of the drive wheel. On top of that, it had an uncompromising density and a beauty that remains peerless to this day as far as chronographs go.

To mark its 25th anniversary this year, A. Lange & Söhne unveiled, along with the first white-gold Datograph Up/Down, the Datograph Perpetual Tourbillon Honeygold “Lumen” in a limited edition of 50 pieces. The fact that it pretty much stole the show at Watches & Wonders this year despite being a variation on an existing model says a lot about its magnificence and just what the convergence of three cherished hallmarks – Datograph, Honeygold, Lumen – can do to stir hearts. Even though it is priced to profligacy, to see it is to love it.

Datograph Perpetual Tourbillon

The triple-complication Datograph Perpetual Tourbillon was first introduced in 2016 in platinum with a black dial, followed by a white gold version with a salmon dial in 2019. The movement within these watches was the calibre L952.2. According to Lange’s numbering system, it is based on the Datograph Perpetual movement, the calibre L952.1, which is in turn based on the on the L951.1 in the Datograph. However, the L952.2 has all the updates seen in the second generation Datograph Up/Down calibre L951.6, including a free-sprung in-house balance wheel with inertial gold weights, refinements across the levers as well as a longer power reserve. Notably, it has a power reserve of 50 hours compared to the Datograph Perpetual’s 36 hours. In the Datograph Perpetual Tourbillon Honeygold Lumen, the movement does away with the power reserve indicator while the calendar discs are lumed, hence the movement was named the L952.4.

To recap in brief, the Datograph is as technically elaborate as one can hope for in a traditional, high-end manually wound chronograph, in that it has instantaneous jumping minutes, a flyback function and a clutch lever that pivots concentrically with the axis of the drive wheel for better transmission quality. In fact, these were the qualities I had instinctively described to an up-and-coming watchmaker without missing a beat when asked what my ideal hand-wound chronograph would be, which goes to show how the Datograph has, for better or worse, come to shape our expectations.

This combination is incredibly hard to come by, even 25 years on, to say nothing of the movement’s peerlessly beautiful architecture and decoration. The Datograph Perpetual Tourbillon combines the chronograph with an instantaneous perpetual calendar and a large stop-seconds tourbillon that houses a 2.5 Hz balance. While they aren’t exactly exotic, they are complete in what each offers visually and technically with respect to traditional watchmaking excellence.

The goal of the calibre L952.4 was to preserve the fabled chronograph works of the Datograph, while accommodating complications. Hence, it retains the same wheel train and much of the same chronograph mechanism but with a different plate and bridge design. However, in maintaining the same large-diameter balance wheel with a frequency of 2.5Hz, it required a large tourbillon cage to encircle the periphery of the balance. Therefore, the movement had to be enlarged slightly from 30.6mm to 32.6mm. Additionally, extension wheel/s had to be added after the fourth wheel to traverse the distance to the cage pinion. The result is a beautiful and satisfying large tourbillon with a slow-beating balance wheel supported by a large open-worked black-polished cock.

The tourbillon has a stop-seconds function which was patented in 2003 and first made its debut in the Cabaret Tourbillon in 2008. When latter was unveiled, it was the first hacking tourbillon in watchmaking. This simple but ingenious mechanism relies on an asymmetrical V-shaped spring that can adapt to the contact surfaces on which both arms come to rest, be it cage pillar or balance.

On the dial side of the movement is the instantaneous switching perpetual calendar with a big date, day, month, leap-year indicator, moon phase as well as day/night indication. Notably, unlike the Datograph Perpetual which has a dragging display that changes gradually around midnight, the octagonal tens date disc and a circular units disc, along with analog day and month hands in the Datograph Perpetual Tourbillon are driven instantaneously to their next positions at midnight. This is accomplished with a spring that stores energy and then released at midnight to advance all the calendar indications simultaneously in an instant.

While the calendar mechanism in the Lange 1 Perpetual Calendar relies on a large peripheral 12-month program wheel that doubles as the month ring itself, the calendar Datograph Perpetual Tourbillon adopts a more traditional format with a 48-month program wheel with the leap year encoded in it.

Lumen & Honeygold

A perpetual calendar is the most complex of dial-side complications, making it particularly suited for the Lumen treatment. This treatment is characterised by a smoked sapphire dial that enables UV light to pass through to charge the various luminescent elements beneath. Prior to the Datograph Perpetual Tourbillon, there have been five Lumen models: the platinum Zeitwerk (2010), Grand Lange 1 (2013), Grand Lange 1 Moon Phase (2016), Datograph Up/Down (2018), and the Honeygold Zeitwerk (2021). The Datograph Perpetual Tourbillon, however, offers the most under-dial activity.

Luminous material is applied to the discs of the big date, along with the leap year and day-and-night indicator wheels. The moon phase wheel is made of tinted sapphire and treated with the same material. The tachymeter scale is printed on a German silver ring and is fully lumed. The chronograph counters, featuring luminous co-axial discs for the calendar are inlaid into the crystal dial. The effect of layering and coating various different materials produces a green glow that varies in hue and intensity, creating a visually organised display even in the dark.

While the luminous treatment transforms the appearance of the watch at night, it is equally mesmerising in daylight. The contrast between the translucent monochromatic dial and the soft, warm tones of the Honeygold case and dial furniture is unusual and very beautiful.

This makes it the fourteenth Lange watch and the second Lumen model to be dressed up in the company’s proprietary alloy. While the exact composition remains a secret, Honeygold is known to be o be nearly twice as hard as standard gold alloys and more durable than platinum. Its gentle, pleasing tone is incomparable; it is neither as rosy as rose gold nor as brassy as yellow gold.

The case measures 41.5mm in diameter, just 0.5mm larger than the Datograph Up/Down, and has a height of 14.6mm. It is no doubt a thick watch, but a watch with three traditionally executed complications was never intended to be an exercise in ultra-thin watchmaking and the height-to-width aspect ratio actually feels quite harmonious. In addition, it has a thick, polished domed bezel and a raised flange on the case back to accommodate the movement, resulting in a relatively slender case middle, which is further emphasized with a contrasting satin-brushed finish.

Dressed to the nines

As with almost all Lange chronographs, the view on the back of the watch is arresting to the point that it’s become cliché to say so. One of the most obvious traits that distinguishes it from other chronographs is its unassuming density. Not just levers, but also springs are shaped into elegant forms that exhibit a narrow profile in plan view but with substantial height in cross-sectional view. The clutch lever alone is particularly elaborate. It consist of a lower and upper part assembled by a screw. Its semi-circular pivot moves around a jewel setting screwed to the drive wheel bridge that sits above the plane of the column wheel, thus the clutch lever requires two levels to reach the column wheel. While this is purely functional, both parts are visible and decorated, and the upper part forms a complex shape that lends itself to four sharp internal angles.

The majority of the parts are brushed, while others such as the claw shaped flyback lever and the springs mounted directly on the bridges are black-polished. Most striking of all is the large black polished steel tourbillon cock which has been open-worked to showcase inward anglage while the base of the cock is decorated with hand-engraving. The finishing on the cage itself is also notably fine.

And then there’s the usual lyrical use of colours where blued screws and gold chatons adorn German silver movement plate and bridges. It all makes for a startling reminder that nothing has surpassed this amount of decorative effort in a chronograph in the last 25 years, making it still novel in that sense.

There are hype watches, and then there are watches that deserve the hype. The motivations for buying a Datograph Perpetual Tourbillon are clearly going to be fundamentally different from those for buying a typical hype watch. With that said, €620,000 is eye-watering; in fact, it costs more than double the price of the white-gold, salmon dial version launched in 2019 and about a third more than the Louis Vuitton x Atelier Akrivia LVRR-O1 Chronographe à Sonnerie.

However, it is worth remembering that we’re living in a time where there’s a chance you could drop the same amount of money and receive far less intrinsic horological value, and this is especially true on the secondary market with, of all watches, time-only. Thus, it is not completely out of order in the grand scheme of things. To the Lange devotee, the horological content along with the combination of three signatures of the brand might seem like a fitting culmination of a collection, and to the newcomer, it could be an unadulterated way to mark 25 futile years spent searching for an alternative.

Tech Specs: A. Lange & Söhne Saxonia Datograph Perpetual Honeygold Tourbillon Lumen ref. 740.055FE

Movement: A. Lange & Söhne L952.4, manually wound, 50-hour power reserve; 2.5 hz (18,000 vph)
Functions: Hours, minutes, seconds; one-minute tourbillon with stop seconds; flyback chronograph with precisely jumping minute counter; tachymeter scale; perpetual calendar with outsize date, day of week, month, leap year; day/night indicator; moonphase display
Case: 41mm x 14.6mm, Honeygold
Dial: Sapphire crystal
Strap: Alligator, brown
Availability: Limited to 50 examples
Price: €620,000