New moon

Watch news and tools for
collectors and the curious.

Accuracy

How many seconds a day your watch gains or loses, heard through your phone’s microphone.

Greubel Forsey GMT Balancier Convexe GMT Balancier Convexe
Greubel Forsey · GMT Balancier Convexe

GMT Balancier Convexe

Change

Somewhere quiet, lay the watch caseback up on something soft. Rest the bottom edge of your phone on the caseback and keep both still.