Professional, as in professional. In terms of practicality, there aren't many modern mechanical diver's watches on the market that can match the Oris Aquis Pro Date Calibre 400, powered by Oris's in-house Caliber 400. We got our hands on this watch and reviewed it in detail.
Text by Alexander Krupp
Article published on June 2022, 1
High water resistance of 1000m and user-friendly design
Comparing the Oris Aquis Pro Date Calibre 400 to a regular diving watch is like comparing a fully equipped professional diver to a recreational scuba diver. Because the harsh conditions of professional activities, such as laying deep-sea cables or repairing underwater pipelines, require equipment that can withstand higher pressures while still ensuring maximum safety and ease of use.
Our test watch has all of these features. The case is water resistant to a depth of 1000m and is extremely durable. The bezel, which measures dive time, and the rubber strap are equipped with a patented safety mechanism. Everything from the bezel to the crown and clasp is user-friendly.
Rugged case
The large 49.5mm case is crafted from DLC-coated titanium and is water resistant to 1000m, making it durable enough for sporting or professional use in any situation. The screw-down crown is equipped with shock protectors on both sides. The bezel's graduated insert is made of scratch-resistant ceramic. Oris has applied an anti-reflective coating only to the dial side of the curved sapphire crystal, which has two advantages. First, only diamonds can scratch the surface. Second, it eliminates the blue glare that can be a nuisance on black watches, even in changing lighting conditions, which is common in many double-sided anti-reflective watches.
The case back is curved and fully screwed down, making it watertight. The depth of the six grooves used to open the case indicates just how thick this screw-down case back is. Incidentally, the back also features a circular scale for converting feet to meters. While this is an interesting addition, the scale's small size and the thickness of the black DLC coating make it difficult to read.
Maximum safety
In addition to high water resistance, it's also important for a diving watch to have a bezel that can only be turned counterclockwise. For example, if the diver's equipment rubs against the watch during a dive and the scale shifts, the bezel may indicate a longer interval than the actual dive time. As a result, the diver will surface earlier than originally intended, but will not be delayed. Another effective safeguard is the use of a rotating inner ring, which can be fixed with the crown after setting to prevent accidental rotation.
Oris achieves both of these protections with a patented mechanism called the Rotation Safety System. It consists of a metal ring with a grooved rubber coating around the rotating bezel. When the ring is pulled upwards, it engages with the groove in the bezel that indicates the dive time, allowing it to be reset in tandem with the minute hand. When the ring is pushed in again, the bezel locks into place and points to the desired time. The ring can still rotate, but it is no longer linked to the dive time scale.
But what if you forget to push the ring in before diving? Even in that case, the watch offers the same level of safety as a standard diving watch. Despite the safety system, Oris also uses a unidirectional rotating bezel.
Another important safety feature of professional diving watches is the helium escape valve, which our test model also features. This valve allows gas that builds up inside the watch case during days of pressurized deep-sea operation to escape safely as the watch and its wearer ascend inside the diving bell. This feature prevents excessive pressure from building up inside the case when the outside air pressure drops, which could cause damage or dents to the watch's crystal.
But when it comes to safety, that's not enough. With the rotating bezel out of the way, Oris has also devised a clever, patented solution for the strap: an arrow-shaped strap tip to prevent the strap from slipping off the clasp. This "safety anchor" is useful if you don't properly insert the pin into the desired hole when adjusting the strap length, or if you don't properly fasten the clasp. While each of these errors is unlikely, and the chances of both occurring simultaneously are extremely slim, as the saying goes, "better safe than sorry." Despite the safety anchor, the strap can still be fully opened, for example, to view the conversion scale on the case back. To do this, simply squeeze the arrow-shaped strap tip and slide it away from the clasp.
Convenient operability
The clasp not only enhances security, but also offers other features that enhance practicality and comfort. To open the folding clasp, simply press the safety pusher on one side, making for a comfortable and convenient design. Our test editors were impressed with this system, describing it as highly reliable. There's also a quick-release extension that can be extended up to 18mm in five positions, allowing you to lengthen or shorten the strap without removing it from the watch.
The watch's user-friendly design is further enhanced by the large, easy-to-grip screw-down crown. The black DLC-coated crown is perfectly sized to fit the watch's dimensions, ensuring ease of operation. The rotating bezel is also extremely user-friendly. The rubber is easy to grip, and the deep grooves on the ring provide a non-slip feel.
Modern Movement
One quirk of the in-house Caliber 400 may be disconcerting to some users: when you pull out the crown to set the time, the minute hand jumps forward by about a minute and a half. This seems to be specific to the Caliber 400. It's not a serious issue, since the hand doesn't move when you push the crown back in. However, if the watch gains a few seconds over the course of a few weeks and you want to pull the crown out to adjust it, you'll have to wait a bit before pushing it back in, which is necessary from time to time. Our test watch was accurate to +0.5 seconds per day in our measurements, but during wear testing, it improved to +2 to +9 seconds over the course of several weeks.
Other than the test watch's tendency to advance a little, there was nothing particularly appealing about the Oris Caliber 400. The in-house movement, released in the fall of 2020, boasts a long power reserve of approximately five days, significantly improved magnetic resistance, and a long service interval of 10 years. For this reason, Oris offers a 10-year warranty, but recommends annual water resistance checks.
It's big but not heavy
Although my test watch wasn't yet at the 10-year mark required to verify the recommended maintenance interval, and because concerts were canceled due to COVID-19, it wasn't exposed to the strong magnetic fields of loud speakers found in concert venues, the long power reserve was still a major advantage, making it extremely convenient for leaving the watch alone for a few days and then wearing it again.
While you won't need to remove the watch for showers or swims, you probably won't wear it to business meetings, galas, or other special occasions. Its sporty tool watch aesthetic means it's difficult to slip under the sleeves of a dress shirt or sweater. While its 49.5mm diameter and 17.5mm thickness aren't small, the lightweight titanium case ensures it's not uncomfortably heavy. At a relatively light 158g, it sits comfortably on the wrist. And if the strap is still too long even after adjusting it to the last hole and the narrowest step on the quick-extension mechanism, simply cut the rubber strap and reposition the clasp. Everything is carefully thought out and not by chance. Professional divers, after all, tend to avoid unexpected surprises.
Accuracy stability test
(daily difference in seconds)| on the dial | +1 |
| Below the dial: | −2 |
| Above 3 o'clock: | +1 |
| Below 3 o'clock: | +3 |
| 3 o'clock left | +3 |
| 3 o'clock right | −3 |
| Maximum posture difference: | 6 |
| Average daily difference: | + 0.5 |
| Average swing angle: | |
| Horizontal posture: | 311° |
| Vertical posture: | 288° |
Score
| Strap & Clasp (Max 10Pt): | The quick adjustment of the rubber strap and the safety anchor to prevent loss are highly appreciated. 9 points |
| Case (10): | 1000m water resistance, automatic helium escape valve, patented ceramic inlay and safety bezel with luminous scale. 9Pt |
| Dial and hands (10): | The indexes, hands, and five wave patterns are carefully crafted. |
| Design (15): | Tool watch specifications with no unnecessary features. 12Pt |
| Visibility (5): | Perfect visibility is ensured for everyday use, and although the glow from the luminous paint is weak for the first 20 minutes of a dive, the visibility of the minute scale is above average even when diving. |
| Operability (5): | The large screw-down crown, rotating bezel, and user-friendly strap make operation easy. The minute hand tends to return when the crown is pulled out. 4Pt |
| Wearability (5): | It won't fit under a shirt cuff or sweater sleeve, but it's surprisingly comfortable to wear thanks to its lightweight titanium construction. |
| Movement (20): | The in-house Caliber 400, which runs for approximately five days without additional winding, is highly anti-magnetic and requires maintenance only every ten years. |
| Accuracy (10): | The average +0.5 seconds is within the acceptable range for timing performance, and the difference in attitude is small at 6 seconds. |
| Overall rating (10): | The price is on the high side for Oris, but it is reasonable compared to the contents. |
| total: | 83Pt |
*This article is a translation of the German version of Kronos.
http://www.webchronos.net/features/59901/
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