Timing

In watchmaking, timing is not a single concept: it is a family of functions that share the same purpose — measuring an interval — but diverge profoundly in mechanism, direction, and context of use. From the bench, I distinguish at least three categories: progressive timing (starting from zero and counting forward), countdown (starting from a value and counting backward), and rate verification timing, which concerns the movement itself more than the external event.

Progressive timing is that of the classic chronograph. The flyback function is its most useful variant in operational contexts: a single command resets and restarts simultaneously, without the stop-reset-start cycle. In sailing contexts, countdown is added; in the new generation Yacht-Master II it is programmable via lateral pushers after abandoning the Ring Command. The countdown bezel, like that of the Favre-Leuba Deep Raider Revival or the Seiko Prospex SPB515, transfers this logic onto a rotatable physical scale: you align the luminous triangle to the current minute and read the remaining time without looking at the seconds hand.

The unidirectional 60-minute bezel on divers — from the Doxa with its luminous dot to the 120-click bezel — is safety timing: the prohibition on clockwise rotation prevents inadvertently underestimating elapsed time. When the bezel is internal and operated by a secondary crown, as in the Bremont with Roto-Click or the Mido Multifort 8 Two Crowns, protection against accidental rotation during diving or flight is added.

Precision sports timing operates on a different scale. Tissot in professional cycling uses photocells and 10,000 frames-per-second cameras; Omega in swimming developed tactile touchpads that stop the stopwatch at hand contact. At movement level, the eccentric adjustment screws on the balance — the eccentric timing screws — are the tool with which the technician corrects oscillation frequency: by acting on their position, the center of mass of the balance is shifted and the rate of the caliber is modified.

Resonance is a separate case: two balance wheels oscillating in phase correct each other, reducing cumulative error. Huygens observed it in pendulums; F.P. Journe applied it to the wrist in 2000. It is not timing in the sense of measuring an external event, but timing in the deeper sense: the intrinsic stability of the movement's cadence.

The MB&F Sequential with Twinverter pushes simultaneous timing to its logical limit: four operating modes — independent, split-second, lap-timer, cumulative — selectable from a single binary switch. It is the high end of a line that begins with an aluminum bezel and an egg-cooking scale.