Light on your wallet - intro

Divers get through a lot of torches. Why They get lost, they flood, theyre bought only as back-ups, they become obsolete. So it may be sensible not to sink all your cash into a supertorch but to make your choices from the budget end of the market. Can you find a good, reliable light there John Bantin tests 38 torches ranging from£11 to£150


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How did they perform Comparison Table

THERES A BIG DIFFERENCE BETWEEN HAVING A LAMP THAT WORKS and being left in the dark. The primary function of a diving torch is to allow you to see your gauges, to find your way and be found if needs be.
When it comes to comparing a range of torches, unfortunately the crucial aspect of reliability is the one area that must be left to shrewd guesswork.
Suffice to say that any item with an airspace that is taken under water is likely to flood at some time, so perhaps it makes more sense to carry a number of less expensive lamps than to invest all your eggs in one possibly leaky basket.
At the Diver offices we seem to be inundated with hi-tech, high-output, high-priced underwater lamps, but for this comparison we looked at the bottom end of the underwater lighting market, at those units costing from as little as£11 to a maximum£150.
Lamps tested ranged from tiny back-up lights, often of the type you might use as a last resort, to full-sized lanterns by the light of which you could expect to navigate any dive.
We have criticised some of the back-up lights for their method of switching off. Many use a system whereby the front shroud screws down onto the sealing O-ring to make a good seal while allowing the bulb to make a good electrical contact.
This is all well and good for a lamp switched on before entering the water, but less so for one you want to leave switched off. Often the seal proves not to be watertight, or the increasing water pressure causes a contact while out of sight in your pocket, which runs down the little batteries so that they go flat. Either way, the back-up might prove unreliable when you need it.
Burntimes can be very important. Rechargeable lamps tend to offer the greatest light output but with the least duration. A lamp loaded with a lot of big alkaline batteries can see you safely through numerous dives before those batteries need replacing.
The newcomer to the market is that type of lamp equipped with high-output LEDs. These tend not to give a very concentrated beam but their duration can be almost forever.
There is a trade-off between light output and burntime. Some lamps are very bright but with a short burntime. Some seem rather puny but go on for much longer.
Some lamps have two bulbs fitted and allow the user to switch between a higher and lower output. Where this was the case, we used the brighter setting for the test.
Many rechargeable lamps come with fast chargers. However this is not usually the case at the less-expensive end of the market and lamps often need charging for anything between eight and 14 hours.
If you are on a liveaboard this can be of consequence, especially if the boats generator is run only for short periods of time. You may be better off with a lamp with alkaline cells.
Some lamps use nickel-cadmium batteries of the same dimensions as alkaline cells and vice versa. Before interchanging power supplies, it is a good idea to check that the bulb fitted is suitable for the alternative.
We measured the light output of each lamp through water over a 1m distance. We also looked at the weight of each lamp while submerged.
This is important, because some of the big heavy lamps displaced a lot of water and became quite lightweight, whereas those with compact dimensions weighed a similar amount as they did in air.
Some had a big airspace within the reflector, which made them unbalanced and hard to handle. A positively buoyant lamp cannot be put down and can be difficult to locate in the dark if it is floating tethered above your head.
We compared the spread of each beam, and also its quality in terms of evenness.
Some lamps gave a good hotspot but with a large peripheral halo. These halos can be useful. Its comforting to know what might be loitering just out of the line of the main part of the beam.
The brightest lamp tested here was found to be 500 times brighter than that with the lowest output. The light was sometimes delivered in a tight bright cone and by others in a broad even flood, while some beams were very patchy indeed.
Compare the quality of light emitted by studying the photographs of the beam spread, but bear in mind that this does not indicate brightness - only how the light is delivered.
So when comparing, also bear in mind the figure for brightness of the hotspot and its diameter measured under our controlled conditions. The wattage of each bulb was not always relevant to ultimate light output, so we have excluded that information.
The size of the reflector no longer indicates efficiency. Smaller bulbs make reflector design more efficient and output that much greater. We give you the diameter of the reflector merely to help you judge the size of a lamp from its photograph.
Brightness of a diving lamp (as opposed to a video light) is subjective, because our eyes can adapt to such a wide range of light levels. You will think your lamp puny only if you are enjoying the output from the far more powerful lamp of your buddy.
A lot of extremely bright but inevitably expensive lights are available but none of those tested here was bright enough to turn a night-dive into a day-dive, and none was good for lighting up subjects in a full spectrum of colour during a daylight dive in tropical sunshine.
However, we deduced that the light output of some was not sufficient for them to be considered as lamps for routine use. Those that revealed brightness factors of less than 50 were consigned to the category of emergency back-up lighting.
We show here the results of a single comparison test. Naturally one set of conditions can be very different to the next, so dont be tempted to try to compare the results we publish here with any from elsewhere, even from previous Diver magazine tests.


CONTACT
Aqualung UK 01162 124200
Beaver 01484512354
Birchley 01452 855312
Blandford/Peli Products 01923 801572
CJ Evans 01202680522
Dive Lights International www.niterider.com
Gilan 0031 113 670431
Hydrotech 01455 274106
Lumb Bros 0161 6815790
Oceanic SW 01404 891819
Sea & Sea 01803 663012

How did they perform Comparison Table

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