What is a chronograph watch?

At Watch.co.uk, the chronograph is the most popular type of men's watch next to diving watches and smartwatches. But what exactly is a chronograph and how does it work? In short, a chronograph watch is a watch with a stopwatch function. But you can do a lot more with a chronograph... 

When is a chronograph watch useful?

The first chronograph available to the general public was a pocket watch designed to time horse races. At the beginning of the 20th century, the chronograph function was added to wristwatches to allow drivers and pilots, among others, to time themselves and each other. Astronauts also made use of the chronograph function in the 1960s.

But the function is also useful if you do not use a chronograph professionally; Runners can measure how long they take over a given distance. For racing fans and swimmers, a chronograph is useful for recording split times. And the chronograph has even more functional uses; For example, they are also used in heart rate measurements by doctors (pulse meter) and divers use a chronograph to time actions during a dive.

In this blog we only discuss the 'traditional' analog chronograph. If you want to take very detailed time measurements and save data, it is recommended to choose a digital chronograph with memory, such as a lap timer or Bluetooth connected watch .

How does a chronograph work?

Using a chronograph is very simple. Just press the top start/stop button on the side of the watch to start or stop the timekeeping. The bottom button on the side of the watch resets the stopwatch to zero, ready for the next measurement.

How to read the time on a chronograph

A chronograph works just like any other watch with hour, minute and second hands.

Most watches with a chronograph function also have three sub-dials containing a second hand, minute hand and hour hand that separately indicate the elapsed time.

There are also chronographs with an extra central second hand. This long second hand that in this case measures the whole seconds. This second hand is activated when the stopwatch is started.

Are there other types of chronograph watches?

Besides the 'normal' chronograph, there are three other variants of this type of timepiece:

The flyback chronograph; Originally designed for military pilots to save time, the flyback mechanism allows the timer to be started and restarted with a single push of a button.

The 'jumping seconds' chronograph is a hand that can stop at fractions of a second (quarter, one-fifth, one-eighth, and tenths of a second) to measure extremely precise time.

The split second chronograph: intended to measure time averages using a second second hand, which rotates in tandem with the first second hand. When the button is pressed, the second second hand stops, while the first second hand continues. When the time has been recorded, pressing the button causes the stopped hand to automatically catch up with the other hand. This function is especially useful for recording split times or lap times.

A jumping seconds or split seconds chronograph is rare and can generally be found in the top segment of Swiss watches.

Measure distance and speed using a tachymeter scale

So using a chronograph is quite simple. Basically it's just a stopwatch, but when combined with the tachymeter that is printed on the bezel of the watch on many chronographs, your chronograph becomes an instrument with which you can measure distance and speed.

Before the cockpit was full of digital gadgets, the tachymeter was widely used by pilots, for example to check how much fuel they had left for the distance covered. Soldiers used a tachymeter to calculate how far they were from enemy guns. That's why you often find a tachymeter scale on pilot watches and military watches.

Using the tachymeter scale to measure speed

Your speed can be calculated by the formula T = 3600/t where 'T' is the number on the tachymeter, 3600 is the number of seconds per hour and 't' is the time in seconds measured by the chronograph. Once you've measured the time it takes you to travel a mile and divide 3600 by this number, that number on the tachymeter shows the speed you're driving in miles per hour.

To measure the average speed of an “object” like a racing cyclist using a tachymeter, you need to know the set distance between two points. Suppose you are standing by the road and you know that the distance between two lampposts is 500 meters (0.5 km). As soon as the bike passes the first lappost, press the start button. When the bike passes post two, stop the chronograph. When the second hand on the tachymeter scale shows 80, this means the cyclist has traveled at an average of 40 km per hour.

Using the tachymeter to measure distance

To measure distance traveled, you must first know your cruising speed and it must remain constant. When you drive on the highway at a constant speed of 60 miles per hour, you start the second hand of the chronograph. When the second hand indicates 60 on the tachymeter scale, you have traveled 1 mile.

With the chronograph you can also measure how far lightning is away from you. Start the chronograph when you see the flash of light and stop it when you hear the bang. Sound travels about a kilometer every three seconds. So, if you want to know how far you are from the lightning, divide the number of seconds by 3.

There are many more calculations you can perform using a tachymeter scale. More about that in a future blog.

Chronograph or chronometer watch?

The terms chronograph and chronometer are often confused. A chronograph is a watch with a stopwatch function. A chronometer is a very precise analog watch with an inspection certificate issued by the COSC (Official Swiss Test Institute). With this certification, the organization declares that the movement meets a series of extremely strict requirements, after a series of 7 technical tests carried out in a laboratory.

A chronograph can therefore be a chronometer, but a chronometer is not always a chronograph. In the Certina watch collection you will find several chronometer chronographs for men and women.

Which is the right chronograph for me?

Many customers choose a chronograph because of the unique appearance of this type of watch. Sporty or very classic. Wearing comfort and size also play a role in their choice.

If you really want to use the chronograph for time measurements, it is important that you determine in advance which specifications the watch must meet. For example, pay attention to the maximum time that can be measured. Most traditional chronographs measure up to 24 hours, 60 minutes and 60 seconds. 

Also check whether you can easily read the subdials and what the ease of use of the push buttons is. Other useful features include luminescent markers so you can read the watch in the dark, water and shock resistance if you're going to use the chronograph underwater or outdoors, and a tachymeter if you plan on measuring distances and speeds.

On our chronographs page you will find all chronographs in our range.