Split Seconds, On Split Seconds Chronographs

A watch lover on IG wants to know why one of the great classic complications don't get no respect.

Not long ago I did something I’ve never done before: I did an AMA (Ask Me Anything) on Instagram. The questions were fascinating. They ran the gamut from highly technical watch questions to highly personal (someone asked if I have any Asian heritage; yes, Filipino on my mother’s side. The family story is that they originally emigrated from China but all family records were destroyed during the Second World War).

One of the questions more on the technical and historical side, was from @mark_lew, who asked, “Why is the split-second chrono so underrated?”

I think there are two answers to that question. The first is that it’s not entirely clear to me that the complication is underrated.

The split-seconds chronograph is one of the three complications necessary for a watch to be considered, at least in classical terms, a “grand complication.” Patek uses the term “grand complication” for a range of watches that have complicated mechanisms and has done so for many years, but if you are a stickler for traditional usage, this is what “grand complication” means:

A watch with a perpetual calendar, a chiming complication (at least a minute repeater; grande et petite sonnerie watches are of course allowed as well, although there may be some debate about alarm watches and hour strikers) and a timing complication – usually, a Rattrapante chronograph.

The second answer is that it is underrated. Here is why this might be the case.

The Rattrapante chronograph is an odd bird, and what exactly it does is harder to understand, at least in some ways, than what a repeater or perpetual calendar does. The perpetual is straightforward: You only have to manually re-set the date once every hundred years. The repeater is straightforward: Push the slide and hear the time.

The Rattrapante requires some additional explanation: Do you want to time two elapsed time intervals at once? Maybe the times at which two horses/cars/what have you cross the finish line? Behold the Rattrapante chronograph: When the starter gun goes off, start the chronograph. When the first horse/car/whatever crosses the finish line, press the Split button and one of the two chronograph seconds hands will stop, recording the elapsed time for that horse/car/whatever. When the second horse/car/whatever crosses the finish line, hit the chronograph stop button and you will record the elapsed time for the second horse/car/whatever, AND you can compare the elapsed time for the first horse/car/whatever with that of the second horse/car/whatever.

I have heard it said that any product you have to explain will struggle to find a buyer.

The Rattrapante chronograph takes some explaining, which might be part of the reason that it’s not top of mind in the same way as the repeater or perpetual calendar (frankly, the repeater is not top of mind for most collectors either, which is a terrible shame). It’s a slightly abstract complication – the need to time two successive elapsed time intervals is not something most people run across unless they’re timing a race between horse/cars/what have you, and for air navigation by dead reckoning, the Flyback chronograph makes perfect sense but the Rattrapante, as far as I can tell (non-pilot with some general understanding of dead reckoning) doesn’t.

However, it’s considered one of the top three high complications for a reason. The Rattrapante mechanism is complex and delicate and requires a great deal of skill and care on the part of the watchmaker to set up – what you basically have, in a Rattrapante chronograph, are two chronographs grafted onto each other. The split hand has its own return to zero heart piece, its own column wheel separate from the column wheel that controls the main chronograph train, and an elaborate mechanism for isolating the split seconds hand when it stops, and re-synchronizing it with the main Chronograph seconds register. For all that it seems the most niche in appeal of all the three classic high complications it is in some respects the most demanding. The Rattrapante, certainly, can be industrialized; so can the perpetual calendar (so far the minute repeater resists industrialization; the Tourbillon has not.)

A Rattrapante chronograph is a perfect example of the fact that we shouldn’t be judging complications by parts count. It is, of course, much more complex than a standard chronograph but even a standard chronograph is sort of a miracle – it says something about how hard it is to design a good one that in the history of fine watchmaking we had minute repeaters before we had chronographs, never mind a Rattrapante chronograph. Today they are still rare – I bet that there are more minute repeater watches and tourbillon watches made every year than there are Rattrapante chronographs. The complication has not resisted industrialization in the same way that the repeater or grande sonnerie have resisted industrialization – we have Richard Habring and IWC to thank for that – but the intellectual ingenuity and level of craftsmanship required by a traditional Rattrapante chrono ought to make it much more widely appreciated, understood, and collected than it is right now.

It is a difficult complication – what it does is more obscure than what other high complications do; understanding how it works is a heavy lift. But it is in many respects, the most fascinating of all the three classic high complications (repeater, perpetual calendar, Rattrapante chronograph) if you ask me.