Ressence Launches The Type 5 L Dive Watch, With Full Lume Dial
An oil-filled dive-capable watch from Ressence gets a glow-up.
Ressence launched its first watches in 2010, and although watchmaking in general is an incremental business (even at the high end, or maybe especially at the high end) we had absolutely never seen anything like them before. The first Ressence watches had two internal compartments, with the going train and motion works in the lower compartment, and a system of orbital displays in the upper compartment, which was filled with petroleum oil. The upper and lower compartments are completely physically separated.
The oil plays a trick on the eye – since the refractive index of the oil and the crystal overlaying the display are similar, it looks as if the rotating displays are floating right on the upper surface of the crystal itself. If you have never had a chance to see a Ressence watch in person – and you may have not; production is still fairly small, with the New York Times reporting that the company delivered just 650 watches in 2023 – it’s worth making an effort to see one in person if you can.
The watch is wound and set by rotating the turning caseback. The displays in the upper half are not mechanically coupled to the base caliber – instead, they are coupled by powerful but very small permanent magnets, which are contained in an alloy designed to provide a preferred pathway for magnetic field lines (the same basic mechanism by which soft iron antimagnetic inner cases and dials work).
While Ressence has long since developed other orbital displays that don’t rely on the ROCS system, the oil filled watches still give you a visual effect that really rates the term, “magical” – even after 14 years, the Wow factor is undiminished.
Ressence has just announced a new version of its Type 5 diver’s watch – yes, there is a Ressence dive watch; the Type 5 was introduced in 2015 – and if you like lume, you’re gonna love the Type 5 L.
The Type 5 L follows the same basic blueprint as the very first Ressence ROCS watches. The upper half of the case is filled with oil, with the displays seeming to float on the surface of the domed sapphire crystal. The satellites carrying the displays are made of grade 5 titanium. Minutes are read off the central minute hand, hours off the hour subdial, and there is an oil temperature gauge, as well as a “runner” indication that rotates once every 90 seconds – this is a proof-of-function indicator, which is an essential element in a dive watch (generally this is handled by a running center seconds hand). The largest disk, carrying the minute hand, rotates once per hour, and the smaller displays are geared so that they always remain vertically oriented, so the watch can be read easily.The temperature gauge is calibrated from -5ºC to +55ºC (about 23ºF to 131ºF) and it shows the temperature inside the oil filled compartment, via a spiral of bimetallic metal.
The oil expands and contracts as temperature changes – I would think this is especially relevant to dive watches – and the gauge shows the optimum operating range; changes in the volume of the oil in the upper case are compensated for with an internal bellows system. Ressence loads oil into and seals its cases at -5ºC.
The bezel is unidirectional, with a lume pip at the zero position. The caseback is locked in position under normal circumstances via a sliding switch on the case flank – this is the Ressence Compression Lock System, which compresses the case gasket when locked. The RCLS provides the same water resistance functionality as the screw down crown on a conventional dive watch.
The magic really starts to happen when the lights go down (or when you go down deep, as the case may be). The entire dial is filled with lume – full lume dive watch dials are relatively rare (I’m not sure why, except maybe for the extra cost involved; a full lume dial seems to make an awful lot of sense for a diver’s watch). The effect is really striking, and makes what’s already a highly legible dive watch even more so.
There are many reasons to like a watch. There are technical reasons, involved aesthetic reasons, historical reasons and heaven knows, even spiritual reasons. However before any of the more considered reasons come into play, there is a simple, pure fascination – you know what they say, the heart has its reasons, whereof reason knows nothing. There is something about a watch that glows in the dark – I’m not sure what it is; maybe it has something to do with the combination of light, and coolness. There’s no heat, and the glow is not a friendly reasonable yellow or orange, but an unearthly green. This is all by way of saying that the appeal of lume hits deep – somewhere in the brainstem, maybe where reason also knows nothing – and there is something weirdly benevolent about the friendly green glow, as if you’re in the presence of a kindly spiritual visitation.
There are nonetheless practical arguments for the Ressence Type 5 L. There is the obvious benefit to legibility you get from the full lume dial. There is a benefit to legibility, also, in the ROCS system, which unlike a conventional dive watch, which has air under the crystal and therefore suffers in readability when seen from anything other than a direct full face angle, is legible from any angle. The Ressence Type 5 L also conforms to all the requirements of the international standard for dive watches, ISO 6425, with that one-way bezel, and a water resistance rating of 100M (that is the minimum specified by ISO 6425 and it’s more than enough for recreational and even some professional diving – most recreational diving happens at 40 meters or less).
But you probably won’t think about that too much, unless you’re in that small wedge of the Venn diagram where “Ressence Owner” and “Enthusiastic Recreational Diver” intersect, and honestly I struggle to think of a dive watch that would make a more satisfying desk diver. The ROCS system is as hypnotic as it ever was – it is something like a magic trick, except you lose nothing in enjoyment in knowing how it’s done). And what really closes the deal is that full lume treatment; the Type 5 L is a new member of the class of luminous creatures of the deep.
The Ressence Type 5 L: Case, grade 5 titanium with one way bezel; 46mm x 15.5mm and 100M water resistant. Movement, ROCS 5 system, with winding and setting via caseback RCLS (Ressence Compression Locking System). Magnetic transmission system. Automatic, 36 hour power reserve, running at 28,800 vph in 41 jewels. Price, $39,900; for more info, visit RessenceWatches.com.