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Speaking of sports watches, most people think of chronographs and diving watches. These two watches are typical representatives of sports style. One is reminiscent of fierce racing and wild air travel, and the other is reminiscent of the adventure of Twenty Thousand Leagues Under the Sea. From heaven to sea, everything is possible. The reason why many people abandon formal wear and choose sports watches is not only for matching, but also because of its usefulness in adapting to most scenes. So, as the duo of sports watches, the king of practicality among sports mechanical watches, which one is more useful in daily life, a chronograph or a diving watch?

chronograph

Generally speaking, chronographs are much more useful than dive watches in accurately measuring the time it takes to do something, which is their specialty. Chronographs usually have 2 or 3 sub-dials, among which they have at least two functions: counting seconds and scoring. When the open button is pressed, the pointer of the sub-dial starts to rotate, and the stop button is pressed to stop. From this, the wearer can read how long this period of time is. In the early days, mechanical chronographs were used for timekeeping in sports such as racing.
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Later, watchmakers combined the timekeeping function of the chronograph with some simple mathematical principles to create a wealth of derivative functions. The speedometer bezel is a classic example. The wearer can use the speedometer bezel to quickly find out his average speed over a certain distance.

It seems incredible, but a mechanical watch can also directly display movement speed? In fact, the principle is not particularly complicated. For example, suppose you are driving, starting from point A and ending at point B 1 km away. When you start from point A, press the chronograph and the hands start to work. When you reach point B, press the chronograph and the hands stop. The reading it points to is your average speed during the 1 kilometer journey.

The principle behind it is: If the time it takes you to walk 1 kilometer is 30 seconds, then the distance you can walk in 1 hour is 3600/30=120 kilometers. In other words, your speed at this moment is 120 kilometers per hour. Therefore, the 120-hour speed scale is engraved at the 30-second position, and the other speed scales are distributed in the same way. In this way, a speedometer bezel is created.

In the early days when mechanical watches were popular, this function would still be used in sports such as racing, but now 99% of people won’t use it, because wouldn’t it be nice to directly use GPS to measure speed? However, this function is still retained, just like the mechanical watch is retained, it is no longer so useful, but it has an alternative retro charm.

In addition to speed measurement, the chronograph also derived the method of measuring distance. The watchmaker engraved the distance on the bezel, and the wearer can measure the distance between himself and a certain place by "opening" and "pausing" operations. Sounds even more amazing? The principle behind it is not complicated either. For example, when a soldier sees the light of an exploding artillery shell in front of him, he presses the chronograph, and then presses the stop button when he hears the explosion. At this moment, the timer pointer points to the distance between his position and the explosion point.

The principle is: the speed of light is faster than the speed of sound, so the speed difference between the speed of light and the speed of sound can be used to calculate the distance. The speed of light is 300,000 kilometers per second, which is too fast so it is regarded as infinite; while the speed of sound is only 340 meters per second. The time difference from "seeing" to "hearing" can roughly calculate the distance between two places. Since sound travels 20 kilometers per minute, the scale of the ranging bezel at the 60-second position is 20.

Of course, no one would use such a "clumsy" tool in modern warfare. Most watchers use it to measure the distance of thunderstorms: when you see lightning, press the chronograph, and when you hear thunder, press and hold. Then you can get the distance between your location and the location of the thunderstorm. There are also other small applications in daily life, which are very interesting.
The chronograph also derives a pulse calculation function. The watchmaker engraved a series of pulse readings on the bezel, and the doctor can use the pointer to visually display the patient's pulse number by pressing the "Open" and "Stop" buttons. The mathematical principle is similar to that of the speedometer bezel, so I won’t go into details here. The variety of ways to play with chronographs is amazing, and you have to admire the whimsical ideas of the watchmakers. But this does not mean that chronographs are necessarily more useful than diving watches.

Compared with diving watches, chronographs have two fatal flaws: First, they are fragile and the timekeeping components are extremely complex, so excessive frequency of use, external impact, etc. can easily cause damage to the movement. There is a watch friend next to me who spent 50,000 yuan to buy a chronograph from a well-known brand. After buying it, he couldn't help but play with its timekeeping function. Unexpectedly, the timekeeping hands would not move after a few days. Fortunately, the counter took a responsible attitude and gave him another watch.

The second drawback of chronographs is that they are expensive. Because the components of chronograph movements are complex, precise, and difficult to make, few brands can produce them by themselves. Even if they can be produced by themselves, the cost is high, so the price of chronographs is also higher. For sports watches, being too refined is not an advantage, but hinders usefulness.

diving watch

Diving watches are a hot watch category nowadays. Its biggest features are three: first, it has a waterproof depth that is much higher than that of ordinary watches; second, it has a luminous function so that divers can read the time in dark water; third, it is equipped with a countdown bezel. Specifically, every dive watch is required to comply with a set of specifications in ISO 6425. Includes: waterproof depth of at least more than 100 meters; luminous dial that can still be read from 25 cm away in complete darkness; anti-magnetic level 4,800 A / m... and so on.

The countdown bezel of a diving watch is similar to the timekeeping function of a chronograph, but it is much rougher than a chronograph. The timekeeping accuracy of a chronograph can reach more than a few tenths of a second, while the timekeeping scale of a diving watch can generally only be accurate to the minute.

The scale of the diving bezel is 60 minutes, and the scale interval is 5 minutes. The scale interval of the first 15 minutes will be further accurate to 1 minute. The 60-minute mark, which is what we often call the 12 o'clock direction, will be marked with an inverted triangle symbol. This bezel can rotate.

When the diver is preparing to enter the water, he calculates the necessary time to leave the water based on the amount of oxygen, then rotates the bezel, rotates the inverted triangle symbol to the time point of leaving the water, and then enters the water. Under water, as the minute hand moves toward the inverted triangle symbol, divers can directly see how long they can stay underwater. If you want to use a diving watch to time time, it is also very simple. You only need to rotate it and use the inverted triangle symbol on the bezel as the starting point or end point, and then you can start timekeeping.

Sometimes, the diving bezel can even be used as a GMT. Simply rotate the bezel to the second time zone mark. When using a diving bezel to measure time, the accuracy is of course far inferior to that of a chronograph. But its durability is far superior. Ordinary water immersion and impact cannot affect the diving watch.

Moreover, in daily life, such high timekeeping accuracy as a chronograph is not necessarily needed. To sum up, for non-professionals, diving watches seem to be more useful. However, in certain circumstances, the high precision and versatility of a chronograph are more attractive. In fact, no matter what the results are, the charm of mechanical watches is more about artistry and sociality, and practicality takes a secondary position. No matter how accurate a chronograph is, it cannot match that of an electronic watch; no matter how durable a diving watch is, today’s divers are more willing to use diving computers.

But this does not prevent watchmakers from striving for excellence, repeatedly improving the accuracy of chronographs to a few tenths of a second or even higher, and increasing the waterproof depth of diving watches to more than 10,000 meters... This has little to do with the usefulness of ordinary people's lives, and reflects a different kind of obsession and obsession. Would you choose a chronograph or a dive watch?