What to Look For in a Chronograph
Three subdials look impressive. Knowing what they do — and whether they are doing anything at all — is worth a minute before you buy.
What a chronograph actually is
A stopwatch built into a watch. The pusher above the crown starts and stops it; the one below resets it. The large central seconds hand is the stopwatch, not the running seconds — that is the small subdial that ticks continuously.
Reading the registers
Typically one subdial counts elapsed minutes, one counts elapsed hours, and one is the running seconds. On some dials a register doubles as a 24-hour indicator instead. If a dial has three subdials but only one moves on its own, the other two are chronograph counters waiting to be started — that is normal, not a fault.
The tachymeter
The numbers on the bezel are a speed scale. Start the chronograph at a kilometre marker, stop it at the next, and the seconds hand points at your average speed. Almost nobody uses it. It is there because racing chronographs looked like that, and it still reads well.
Buying one
Check the pushers click positively rather than mushing, that the reset returns all hands to exactly zero, and that the subdials are legible against the dial colour — a lot of chronographs fail that last test in daylight.
Our chronographs run 41–43mm because the registers need the room. The Casio Edifice is solar, so it never needs a battery.