The watches of A. Lange & Söhne very rarely gets a chance to step out of the stoically traditional design language the brand has established since its relaunch in 1994, but one collection from the brand offers a unique respite from it all. Lange’s Lumen series is now in its 16th year since the introduction of the Zeitwerk “Luminous” back in 2010, with its inaugural display of smoked sapphire, blacked-out details, and, of course, luminous numerals for the hour and minute discs. But while that model was the first to be executed, the following Grand Lange 1 Lumen in 2012 was the first model officially given the name “Lumen.”
Last month, at Watches and Wonders, Lange introduced the seventh Lumen in the lineup, with the new Lange 1 Tourbillon Perpetual Calendar Lumen. Following the absolutely bonkers Datograph Perpetual Tourbillon in Honeygold released in 2025 for the Datograph’s twenty-fifth anniversary, this new glow-in-the-dark take on the very complicated Lange 1 model marks a pattern of increasing complication (and resulting price points) for the Lumen series. A closer look reveals that there’s a lot going on, and for nerds, it’s certainly a feast for the eyes.
In person, the cold, austere look of the chunky, 41.9mm case in platinum immediately struck me, as it was a welcome return to the combination of a smoky, black look with white metal from the past two Lumen iterations in Honeygold (that Datograph Perpetual Tourbillon and its predecessor, the Zeitwerk). For a design where the information literally goes to the edge of the dial, the bright platinum frames the month ring of the perpetual calendar nicely. At 13mm thick, the case is certainly not compact, but that’s no surprise to anyone who knows Lange’s complicated watches.
At a glance, there might seem to be an overwhelming amount of information to digest from the dial of the most complicated Lange 1 in the catalog, and the semi-transparent smoked sapphire certainly doesn’t help. This is a perpetual calendar, after all, and that means that in addition to the time displayed in the Lange 1’s typical offset subdial, the watch also indicates the day, the day of the week (in a retrograde indicator at 9 o’clock), the month (in the peripheral ring surrounding the dial, with a triangular pointer at 6 o’clock to indicate the current month), and the leap year cycle (with a cutout cleverly shaped to extend the triangular shape of the month indicator right next to it).
But that’s not all—sitting in a cutout beneath the small seconds subdial is a moonphase and a day/night indicator, now combined into one gorgeous display. Previously, that day/night indicator sat within the time subdial at six o’clock. It’s a great new addition that brings an incredibly whimsical little detail carried over from the non-tourbillon Lange 1 Perpetual Calendar, where the sky behind the moon itself is another layer, transitioning from a clear sky during the day to one filled with stars at night.
Some of the recessed pushers to adjust the calendar indications.
Lume is, as expected, generous on this Lange, especially compared to its more classic creations. Every piece of information for the time and calendar is visible at night, thanks to the special coating of the smoked sapphire that actually allows UV light to enter the dial and charge all the lume during the day (think of the coating as the reverse of what sunglasses do—it essentially only lets UV light in, which helps a lot when you don’t have a UV torch to blast the dial with). The day/night indicator is particularly perfect here, showing a glowing bed of stars at night and a bright, luminescent blank sky during daytime hours, when the owner inevitably cups a hand around the dial to look at the glow every few minutes while wearing it. I wouldn’t blame them at all—I’d do the exact same thing.
The moon hovering above the day/night disc.
My favorite new design element is the way the numerals are treated on the time subdial. Rather than in previous Grand Lange 1 Lumens, where the numerals were printed with lume, the Roman numerals and diamond hour markers are actually applied. This adds an additional dimension to the dial and a bit of light-catching metal, while beds of lume are applied to the underside of the dial and match the shapes of the appliques above. In the absence of light, the lume behind these numerals illuminates, giving an ethereal outline to the dark shapes in front. I love the way this looks, and it’s a great way to keep applied numerals without compromising the “Lumen” of it all. This also extends to the metallic moon of the moon phase, surrounded by a ring of lume.
As expected with most Langes, the caseback is also just as much of a treat to see. Unlike Lange’s manual chronograph calibers, this automatic L225.1 is covered in what feels roughly like one of the three-quarter plates on many calibers, though its sections are nicely broken up by anglage. And as expected in Lange tradition, there are plenty of rubies set within gold chatons and heat-blued screws throughout the Glashütte-striped German silver caliber. You get the added interest of a winding rotor, here in 18-carat white gold with a platinum winding mass screwed in.
Two different prototypes, left and right, show how the engravings can differ.
At this point in the story, you might have forgotten that this watch also has a tourbillon! It’s framed by two beautifully decorated components, a tourbillon cock and an intermediate-wheel cock. When I first saw this caliber, the hue contrast between these two pieces stood out immediately, thanks to its stainless-steel construction. They are black-polished and hand-engraved, with a whimsical field of stars (and one shooting star), so every watch in the 50-piece run will have a unique look. As per another tradition, the tourbillon is capped with a diamond endstone, because why not? Having a tourbillon hidden away in your watch is probably one of the biggest flexes in luxury watchmaking, and here it does well not to detract from the Lumen treatment on the dial side either.
Aside from its decoration, the caliber L225.1 is equally (if not more) impressive mechanically. If you owned this watch, you’d probably want to stay up past midnight every single day, since that’s when the instantaneous jump of all of the calendar indications occurs. So at the end of each month, an impressive amount of torque is required to advance everything from the month ring to the retrograde day-of-week indicator to the oversized date. What I’m most impressed by is the oversized date advancing instantaneously, even in February, from the 28th to the first. The 3 Hz tourbillon is also a hacking one, to add to the list of features here. Lange’s not the only one doing hacking tourbillons these days, but they were the first, so it’s good to see it on this model.
While the overall design of the L225.1 is based on the L082.1 caliber found in the classic Lange 1 Perpetual Tourbillon models, there’s quite a bit that’s changed underneath the hood, thanks to the new day/night integration in the moonphase, the white gold rotor, and the unique tourbillon and intermediate-wheel cock design. A closer look reveals a reconfigured positioning of the gear train. Add in modifications required for the “Lumen” execution, like the additional lume plots and sapphire dial construction, and the parts count jumps to 685, up from 624 for the standard ones.
This complexity, as well as the development of a new, improved caliber for this Lumen version specifically, is certainly a major reason the watch comes with an eye-watering price tag of $530,000. Though it’s still a bit below the $620,000 price tag of the Datograph Perpetual Tourbillon Lumen from a few years ago, this watch’s price marks a significant delta from the standard white-gold model, which is priced at $333,000. Is a two-hundred-thousand-dollar price increase worth its weight in platinum, this new caliber with a day/night indicator, and the glow-in-the-dark treatment?
If you’re feeling déjà vu from the Datograph from 2024, I’ll steer you to Mark’s hands-on with that watch, where I think he makes a great argument in this pricing debate. But put yourself in the shoes of someone with the funds to drop on a piece like this and, well, then there’s nothing else quite like the Lange 1 Tourbillon Perpetual Lumen on the market, is there? In my conversations with people from the brand, they seem extremely confident that they already have the 50 people in mind for such a piece. Mere mortals need not apply, and Lange is not offering this as any value proposition whatsoever.
The unique shift of the sapphire dial in the light.
Put it on, and it’s very easy to understand why. I’ve never been shy about being a huge fan of the Lumen series, because it often is the best showcase of Lange in the context of modern watchmaking. Yes, the brand often sticks to extremely classical watchmaking—it’ll be a cold day in hell before we see silicon hairsprings in a Lange—but the sleek, almost futuristic executions of these Lumen watches remind us that when the brand thinks outside the box, it can do some crazy things. I personally love the juxtaposition of Roman numerals on a watch like this. The watch itself is quite imposing on the wrist in almost 42 millimeters of platinum, also thanks to the Lange 1 design that amplifies the expansiveness of the dial, though a thick strap helps reign in the proportions a bit. Thankfully, a deployant buckle in platinum is also included, an extremely necessary component for balancing the watch’s weight on your wrist.
In terms of legibility, it’s high in contrast, though not the easiest of the Lumen series to read at a glance. That’s kind of an inevitable result of the Lange 1’s asymmetrical dial layout when given this semi-transparent overlay—there are just so many visual elements between the exposed parts that it’s hard for your eyes to actually figure out where to first look for any required piece of information. Yes, it gets easier to read over time, but it doesn’t frame information in the same way that the simplicity of Zeitwerk’s time bridge does, or with the Datograph’s centered hands. Compared to the two Grand Lange 1 Lumens of the past, the subdial for the time is much more open on this one, making the elements blend in a bit more with the caliber itself. But this Lumen has a unique phenomenon thanks to the sapphire dial, which produces a reflective effect at an angle, letting the hands stand out much more when the watch is viewed not straight on. If you’re checking the time on this Lange 1 at an angle, you’ll probably have a much easier view.
If we take the 2024 Datograph and this year’s Lange 1 Lumens as the start of a trend, it’s safe to say that the brand fully understands the weight of desirability these special editions carry, both amongst collectors and in the secondary market. This area always remains a weakness for Lange’s watches in the standard collection. This may mark the end of an era for the Lumen series, which had, in the past, given this exciting treatment to more “standard” and less complicated pieces in the collection, and may mark a new generation where Lange takes the Lumen even more complicated and even more exclusive (this and the Datograph were both 50-piece runs). It’s a halo product for Lange, and the brand is certainly cashing in on it. But with an incredibly unique execution of Lange’s maximalist watchmaking capabilities, it’s certainly a job well done.
