The chronograph, a.k.a. stopwatch for the wrist, is the most popular watch complication. But the many useful applications of the instrument with the two extra push-buttons on the side (By the way some chronographs are also available with single push button, better known as mono-pusher ) usually remain wretchedly unexplored, no matter how proud the owner.
Just for one minute, let us forget those hundreds of functions offered by smart watches, mobile phones, and other digital gadgets.
Simply stated, pressing the start/stop button above the crown couples the chronograph movement to the basic movement of the mechanical watch – which we shall assume is running when this happens. In a quartz movement, the button will start a small motor for the chrono functions. The seconds and fractions of a second are indicated by the so-called chrono centre hand. Two smaller hands on subsidiary dials, usually a 30-minute counter and an hour counter, add the „revolutions” of the chrono centre hand in half-hour increments for a period of up to 12 hours. If the chronograph is not stopped, everything starts from the beginning again, at zero.
The measurement of time can be interrupted at random and re-sumed by pressing the start/stop button or reset to zero (after the chronograph has been stopped) and thus deleted with the reset button below the crown. Apart from stopped times, many chronographs can measure other things: Chronographs with perimetric tachymeter scales will measure the actual speed per hour over a distance of one kilometre or the number of repetitions of an occurrence – parts produced, for instance – within an hour. Some timepieces have (rare) telemetry graduations for determining the speed of sound, or scales that deliver pulse counts and bezels with calculating functions.
The Second Time Zone
Logically enough, a chronograph – because its hour hand completes one full revolution every 12 hours – can also be used like a second watch which continuously displays the time in another time zone. The only drawback: it must be activated precisely when the local time displayed is equivalent to the correct time difference versus 12 o’clock in the other time zone. A simple example: At 6 pm in Schaffhausen, the time in New York is 12 noon. If the chronograph is set in motion at 6 pm Central European Time, its hour hand will indicate the time on the US East Coast. The Coast. The minute reading can be taken from the normal minute hand. This method requires some advance planning, but the chronograph can be useful in that respect as well.
The Appointment Hand
Another extra function which is much easier to deploy consists in using the chrono centre hand as a reminder of a certain hour or minute deadline. For this purpose, the hand is advanced to the respective hour or minute position and stopped there. Since the human mind perceives the 12 o’clock position of the chrono hand as normal, a person’s visual memory will recognize any other position as being abnormal. This is enough to recall an event or appointment associated with the position of the chrono centre hand – for example to activate the chronograph precisely at 6 pm to make use of the second time zone feature.
In this era of disposable napkins and paper tissue, people have abandoned the venerable practice of tying knots in their handkerchiefs as a reminder of something important, but the chronograph offers a viable alternative. In fact, this is one of its most useful complementary functions: an idea, a sudden inspiration, an ingenious nocturnal thought which cannot, at that very pivotal moment, be jotted down on paper, will spring back to mind. How? Press the start button, let the hand run for a few seconds, stop it, and leave it in that position. Later, the next morning, for example the “abnormal” position of the chrono centre hand will remind the owner of the watch, by way of association, why it is not at the normal 12 o’clock position.
A Quick Glance
There are instances when it is useful to know – with one brief glance – how much time has elapsed, particularly when one is pursuing activities which involve speed or considerable physical exertion. In such cases, the positions of the subsidiary hands may be rather difficult to read. The alternative is, prior to the activity in question, to advance the chronocentre hand to the position of the minute hand and stop it there. The minute hand will continue to advance, of course, and the pie slice between then and now, between the minute hand and the stopped chrono hand, will become larger and larger. With this method, it is very easy to quantify the elapsed time of an activity such as jogging or cycling.
The Countdown Function
The same principle can be applied in the even more interesting countdown variation. The chrono hand is advanced to a deadline point within an hour’s time frame and stopped there. Now, the pie slice formed by the chrono hand and the minute hand will gradually become smaller. The human mind has no problems converting this visual magnitude into a time span. It’s easy to tell that the ten minutes planned for the interview are just about up or that it’s time to end the 30-minute workout.
Watchmakers invented the rattrapante or split-seconds hand so that two times could be taken within the same one-minute period. But even an “ordinary” chronograph offers this capability, provided the beginning of the time measurement is at the user’s discretion. The measurement begins as soon as the small seconds hand is at “60”. The first lap time (of the winner) is stopped with the chronograph, the other one is indicated by the small seconds hand.
The Record Keeping Function
Another handy way to use a chronograph is to keep a record of the exact time of an occurrence. An example: You are driving to work and the radio station is playing a tune that has your spine tingling. You want to call the station later and find out the name of the artist. Activate the chronograph and when you have the opportunity to make the call, just subtract the elapsed half hour or hour from the current hand position.
Someone just hit your car on the intersection. You’re busy dealing with the culprit and need to remain composed. Simply start the chronograph at the moment of impact. After all, the police will later want to know exactly when it happened.The same feature can be used in, say, somewhat less altruistic situations, if you – without having to cast a demonstrative glance at your watch – wish to discreetly determine how late Mr. Smith was when he finally arrived at the office or for an appointment.
Courtesy : IWC Schaffhausen