LIGHT AQUA SUN D3 & D6

SOME MANUFACTURERS COMPLAINED TO ME at the international DEMA diving trade show that if they showed products that were not quite yet in production these days, wily oriental enrepreneurs would photograph them and bring out an identical product before their own production line had started to roll.
The Chinese have developed a "can do" reputation for making things. Send them something you want copied and a result will arrive in the UK almost faster than the Royal Mail could get it to you from the local sorting office.
The funny thing is that the Chinese manufacturers themselves also get copied. That's why the first Aqua Sun RC lamp I received looked so familiar. The manufacturer had simply modelled it on another inexpensive lamp that is also made in China, the Aquatec Aquastar 3.
The importer in Britain who had commissioned the manufacture of this product had second thoughts, and preferred to do something better, and so more expensive.
He produced a range of lamps that includes the D3, available in two versions (rechargeable and one that runs on three AAA batteries), and the bigger D5 and D6, both rechargeable and identical in performance, but with a different external finish.
During my earlier career in advertising, I produced many posters adverting JPS cigarettes (I never condoned smoking!), and was naturally rather taken by the finish of the D6 in JPS black and gold. The D5 is slightly different in shape, and finished in silver and blue.
Each comes with a neat holster that will slip onto any webbing, such as that used in BC straps or a weightbelt.
This means that you can stow one discreetly until you need it, so each unit makes a good back-up light, as well as being as bright as most primary diving lights.

Light Source
The single high-output 10W CREE chip LED of the D6 sits behind a steeply convex lens. The sales pitch for so many lamps today revolves around "equivalent watts".
This means nothing, because wattage refers to the amount of electricity consumed, rather than the amount of light produced.
In a conventional tungsten light source, a lot of this electricity is consumed in the production of heat. LEDs produce virtually no heat, so all the power goes into making light.
Light emitted is measured in lumens (700 is claimed in this case), but even this can be misleading. It's the lux that arrive at your subject that counts, and this is where the reflector and lens design is so important.
The D6 is just over 17cm long and around 3cm in diameter. The D3 is smaller at just over 15cm long, and uses a 5W Cree-powered LED that can be switched from full to one-third and one-fifth power.

Power Source
With the rechargeable versions, you take the lithium-ion battery out of the lamp by unscrewing the end section, which is protected from flooding by a single O-ring, and place it in its special charging cylinder.
This is connected either to a mains AC charger or a car's 12V DC accessory charging system - what used to be called a "cigarette lighter".
It takes only three hours to charge the battery fully, and the charger has a red/green indicator light.
Four hours' burntime at maximum brightness might not seem much when compared with 1.5W LED lamps, but it will outlast your dive.

Switching
All three lamps are constructed in aerospace-grade hard-anodised aluminium and have a proper switching system, as opposed to having to unscrew the front section to make battery contact. Of course, this adds to the costs.
A metal rotating collar with detents operates a magnetic reed switch, so there is no risk of flooding from a faulty through-bulkhead connection.
This gives sequential switching with full-, half- and a low-power setting, a flashing signal strobe mode and an SOS flashing mode.
If you don't want to risk rechargeable versions switching on in transit, you simply invert the battery, or carry it separately in its charging cylinder.
The lamps sit comfortably in the hand, though I did need my other hand to operate the switching collar.

Beam
In the few weeks since the first version was sent to me, the product was developed further, with a planar lens to give it a less focused and more evenly diffused beam. The first one had sharply focused the rectangular LED light source in a bright but disquieting and sharply rectangular beam.
Once I got my hands on the final versions, I noted that the beam it produced looked very tight but evenly lit across its hotspot. At around 7500°K, the light is very cold.
It is strange to think that my primary light for night diving will fit into the inside pocket of the jacket I wear on the plane. That's progress, and progress with these guys in the Far East carries on apace. I'm told that the story isn't over yet.
In fact I know that improvements in the magnetic switch will be pending, because once I got these lamps under water, all three versions refused to switch on.
Later, presumably once they had dried out, they decided to switch themselves on in my hotel room, even though the switch was in the off position.
I had to remove the battery in order to get some uninterrupted sleep!

OTHER TORCHES TO CONSIDER:
Lenser Frogman (1.5W Cree), £50

SPECS
PRICE D3, £79; D3 RC (rechargeable), £119; D6 RC (rechargeable), £229
BATTERIES Lithium-ion
BURNTIME 4-12 hours
EXTRAS AC and DC chargers, lanyard and holster
WEIGHT D6, 370gm with battery (D3 200gm)
DEPTH RATING 100m
CONTACT www.aqua-sun.co.uk
DIVER GUIDE
(pending development)