Stepping up a level in complication, we have the perpetual calendar. There are small windows that display the day of the week and the month in the seconds and hours rings respectively, and up at 12 o’clock you’ll find Lange’s signature panoramic big date. Not only does the display feel typically Lange, but it also prioritizes the most pertinent information and gives less real estate to the less used information. Just by the crown you’ll notice the small round window containing the leap year indicator. While this breaks the symmetry of the dial, it’s pretty subtle and doesn’t intrude. All indicators switch instantaneously at midnight to keep things extremely precise.
Finally, the last thing you’ll find on the front of the Terraluna is the power reserve indicator along the bottom of the dial. There is an asymmetric sliver cut out of the dial, below which is a disc numbered up to 14. As the 14-day reserve winds down, the disc moves beneath the aperture, showing you exactly how many days you have left. To keep you from having to do the math yourself, 14 days means a whopping 336 hours of reserve from two barrels.