Prerequisites for Chronograph Dive Watch

[tv.classical]

Hello, this is Classical.
Today I'm going to post about a dive watch with a chronograph function.

A chronograph is a watch with a stopwatch function. This function allows you to start, stop, and reset the stopwatch by pressing the pin on the watch base.

It was first invented for tracking celestial bodies, and later for mass production, it began with the need to accurately measure the time of horse racing, and has since been used in various fields. So you should not assume that it is simply a "Racing watch". Some examples include a tachymeter, which measures speed per hour, and a pulsometer, which displays the number of beats per minute when measured during 60 beats when measuring the pulse. For military purposes, it was used to measure the speed of artillery or missiles.



Dive watches with chronograph functions also began to be mass-produced and were used to measure work time while diving and for various tasks. Dive watches with chronograph functions include IWC's Aqua Timer, Omega Seamaster, Tissot Seastar, Citizen Promaster, Doxa Sub 200, Tutor Black Bay, Mido Ocean Star, Oris Divers Sixty Five, and Panerai submersible , Blancpain Fifty Fathoms, etc...

That's why I inquired with brands that produce chronograph dive watches.

· Mido - responded that the chronograph function cannot be used underwater, and the product description states that it is a marine tachymeter.
· Oris - also responded that it was not possible, and it appears in the manual.
· Citizen - also responded that it was not possible.
· IWC - also responded that it was not possible.
· Doxa - It is officially stated in the manual that it is not allowed.
· Omega - responded that it was available, and it was officially listed in the manual.

Almost all diving watch chronographs are equipped with locks for the standard chronograph pushers. These screw locks do not seal the pushers and users are advised not to operate the chronograph in water. Therefore, although it is called a "Diving chronograph watch", this function can only be used when the watch is out of the water.
Some Dealers and boutiques will tell you that it should never be operated underwater. Many brands even advise against wearing them on surface.


But, If you look at Blancpain's Lettres Du Brassus 15, there is interesting information related to this. You can also see the online version of Lettres Du Brassus on the Blancpain website. You can see here that the Fifty Fathoms chronograph model and the Bathyscaphe chronograph flyback are equipped with sealed pushers that are water resistant to 30 bar, allowing them to be used underwater. As a result, a watch that perfectly fits the description of a "diving chronograph" was created.


Now, since I have a Bathyscaphe Chronograph, I guess I checked it out, right?
I once made a post about practicing scuba while wearing a chronograph in a diving pool. I received many of the same DMs from Instagram. (eg. Is it waterproof since then? Does the chronograph work well? ) At the time, I didn't have any intention of recording it as a video, so I didn't film it.

But this time , I would like to share with you a video I took underwater in the ocean while I was living in the Philippines.
This video you are watching was filmed in the Philippines in November, 2023.

https://www.instagram.com/reel/CzN0J2wLp4x

This is a video of the chronograph operating during a safety stop at 5m after completing a 58minute single gas dive.
Since there was no one professionally taking video for me, I asked a local dive master who was dive with me, but he took the picture of me first without taking a picture of the watch. So, please understand that the video is a little dizzy.
First, press Start. This video shows that after some time has passed, I press the Stop button and then I press the Reset button to move to point 0.

After visiting the Philippines, I stopped by a boutique and had it inspected for waterproofing and errors. I received it today.
There are no signs of water leakage or problems with the water resistance test.

In conclusion,
If you want to get a real dive watch , I highly recommend that you choose a properly made brand like Blancpain or Omega.
And before diving or using it underwater, be sure to check the waterproofness at the frequency recommended by the manufacturer.