Short answer

A replica Rendez-Vous Moonphase My Star is a 1:1 copy of the Jaeger-LeCoultre Rendez-Vous Moon, a ladies' automatic watch with a star-set dial and a moonphase display at six o'clock. The best copies match the 36 mm case, the curved lugs, the applied numerals, and the moon disc. Cheap copies fail in four places: a printed star map instead of a textured one, a moon disc that sticks or skips, a case that runs 1 mm to 2 mm off spec, and a movement that gains or loses more than 20 seconds a day. Check those four items before you pay.

How the moonphase disc works

The moon disc completes one cycle in about 29.5 days. Watchmakers build this with a 59-tooth wheel, which puts the display one day off the real lunar cycle every two years and seven months. On a replica, the disc is driven from the hour wheel through a small reduction gear, so the moon advances one notch each time the hands pass midnight. That is the behavior to test. A correct copy moves the disc one clean step per 24 hours. A poor copy drags the disc, stalls it, or jumps two steps.

What separates a 1:1 copy from a first copy

A 1:1 copy uses a decorated automatic movement with a rotor that mimics the finishing of the original caliber, sapphire crystal, and a case back with correct engraving depth. First-copy watches often use mineral glass, a stamped dial, and a glued moon disc. Ask the seller which tier you are buying and request photos of the case back, the crown, and the moon disc set at a full moon.

Inspection steps

  1. Measure the case across the bezel with calipers and confirm 36 mm, then measure the lug-to-lug distance.
  2. Set the moon to full and note the position of the disc inside the aperture.
  3. Pull the crown to the moon-setting position and turn it forward through five full lunar months.
  4. Run the watch for 24 hours and confirm the disc advanced one step.
  5. Tilt the dial under a lamp and check that the stars are engraved or applied, not printed flat.
  6. Tap the crystal with a fingernail to hear the sharper ring of sapphire rather than mineral glass.
  7. Take a timegrapher reading in six positions and ask for a rate inside plus or minus 10 seconds per day.
  8. Flex the strap at the lugs and inspect the clasp for sharp edges and clean branding depth.

Adjustment and care

Reset the moonphase after a long stop by advancing the disc forward with the crown. Do not set the moonphase between 9 p.m. and 3 a.m., when the reduction gear sits engaged and the teeth can bind. Keep the watch away from speakers, tablets, and magnetic clasps, because magnetism pulls the rate fast. Plan on a service every three to five years, which for most replica owners means a movement swap rather than a full overhaul.