One divers back-up light is anothers primary diving light, if some of the suppliers we approached for this comparison test are to be believed.
Our intention in putting together this review was to look at the sort of lamp you could carry stowed in a pocket or mounted on a BC on every dive. Should that awful moment come when you are unexpectedly left in the dark, you can then find it easily, switch it on and read your instruments as you head back out of the wreck or up to the surface - and still be found by your pick-up boat if its a night dive.
Of course, it would be nice if you could see where youre going, too!
Some people would argue that a redundant diving light should be as good as a primary and that you should always treat your back-up light in the same way as that primary. You should check its operation immediately before diving, and maintain it scrupulously between dives.
Yet many of us stick back-up lights in our pockets and forget them until we need them.
In our test you can see the shape of each beam as it was photographed. Bear in mind that these images do not indicate brightness.
Brightness is not about how much light is produced at the lamp, but about how much light arrives at the object at which you point.
This depends on the efficiency of the lamps reflector, so dont be misled by manufacturers claims.
We give a factor for brightness measured at the end of each beam, shone over 2m. This reveals the number of times brighter each lamp is than the dimmest we tested.
The most important aspect of a back-up light is not how bright it is or the shape of its beam, it is that it works reliably. Many manufacturers unfortunately resort to using the simple screw-down shroud as a switch.
This makes the manufacturing of a watertight product more foolproof, but does not make the light proof against foolish use of it.
Reliability is the one aspect at which we can only guess. The time it takes to test a product for long-term reliability would be more than the commercial life-span of many products, so you will have to put up with educated guesses based on our combined experience.
When Colin managed a busy dive centre, those who rented torches were told to have them turned on before they entered the water and not to turn them off until they were safely out again. He found that he could not trust most divers not to fiddle with them and accidentally flood them.


width=100%BLANDFORD DT-02 £7 (inc batteries)
Its small, its compact and it fits easily in the palm of the hand. On close examination we detected Asian influences, and decided that the unit bore a strong resemblance to an established US-made lamp. It may be basic but it is very cheap and could be a lifesaver if you needed it. The price is remarkable. Put a couple in your pocket and hedge your bets!

BURNTIME 2-3 hours
BRIGHTNESS 8
BATTERIES 4AA
LIGHT SOURCE Halogen
DEPTH RATING 70m
www.blandfordsubaqua.co.uk

width=100%
width=100%SNAP SIGHTS £18 (Batteries extra)
From a manufacturer of inexpensive plastic cameras, this is a very compact little lamp with a rubber front shroud. Twisting the head switches it on, but this can introduce leaks inadvertently and the lamp might switch on unknowingly in your pocket due to the pressure of depth. Its light was not very bright, but it proved to be evenly distributed across its beam.

BURNTIME 6 hours
BRIGHTNESS 4
BATTERIES 4AAA
LIGHT SOURCE Single 1W LED
DEPTH RATING 50m
www.intova.net

width=100%
width=100%BEAVER STELLAR £19 (Batteries extra)
A cheeky lightweight plastic Chinese lookalike of a successful US design, this uses a single Luxeon LED and three batteries with one dummy cell. We felt this cell would easily suffer the drop, plop and curse syndrome during battery changes on boats. A long burntime and not-too-dim performance make this a viable purchase as long as it lasts. Double-O-ring protected, it has a separate switch so should not flood.

BURNTIME 21 hours
BRIGHTNESS 8
BATTERIES 3C
LIGHT SOURCE Single 1W LED
DEPTH RATING 100m
www.beaversports.co.uk

width=100%
width=100%PRINCETON TEC IMPACT XL £26 (inc batteries)
Its not at all that bright, but its unlikely to run out of steam with its inordinate burntime of more than four days! Twist down the front shroud to turn it on, hoping it has not been switched on for the past couple of days in your pocket without you noticing it. That said, this light is something you should be able to stow without it ever flooding, and it will be ready for use the day you need it.

BURNTIME 50 hours
BRIGHTNESS 4
BATTERIES 4AA
LIGHT SOURCE 1W LED
DEPTH RATING 100m
www.princetontec.com

width=100%
width=100%TEK-TITE TREK4 £27 (inc batteries)
More of a light to be seen with than one to see by. It may go on forever, but the light from its unfocused LEDs is probably little more than you might get from bioluminescence at night rubbing your hand on your wetsuit, and that is at full power for the first 20 hours. It gets dimmer after that! It was good for little more than reading your gauges, and the second-dimmest lamp here, but at least we got a meter reading from it.

BURNTIME 20-80 HOURS
BRIGHTNESS 1
BATTERIES 3AA
LIGHT SOURCE 4 LED
DEPTH RATING 300M
www.tek-tite.com

width=100%
width=100%TUSA TC240 £27 (inc batteries)
It looked nice at first but felt a bit flimsy, and the light would flicker at times because of an inconsistent contact. It also dimmed when we put any pressure on the battery area of the lamp casing. That said, it produced a usable amount of light. Twin O-rings and a gasket keep the water out. The TC240 has a simple switch with a lock and contains a spare bulb mounted inside its casing.

BURNTIME 3 hours
BRIGHTNESS 16
BATTERIES 4C
LIGHT SOURCE 4.4W Halogen
DEPTH RATING 50m
www.cpspartnership.com

width=100%
width=100%IKELITE PCm £28 (inc batteries)
Smaller than its siblings tested here, this is a big performer when it comes to light output, although a bigger halogen bulb can never be as accurately focused as a tiny point-source of light, resulting in a slightly patchy beam. The method of shutting its battery compartment tight onto its O-ring inspired confidence in its longevity. With fewer batteries than other lamps in the PC range, its burntime is shorter.

BURNTIME 1.5 hours
BRIGHTNESS 32
BATTERIES 4AA
LIGHT SOURCE Halogen
DEPTH RATING 90m
www.oceanicuk.com

width=100%
width=100%IKELITE PCA £29 (inc batteries)
A very useful little lamp that gives lots of light output, albeit in a rather patchy beam, and is protected from flooding by a unique system for clamping onto its single O-ring. These small Ikelite lamps were among the brightest in this review, and we have had one regularly and successfully in service with DIVER staff for more than a decade.

BURNTIME 2.5 hours
BRIGHTNESS 48
BATTERIES 6AA
LIGHT SOURCE Halogen
DEPTH RATING 90m
www.oceanicuk.com

width=100%
width=100%UK SL4 £30 (inc batteries)
Wow! Its a very old design using old technology, but it works. It provided lots of light in a tightly focused beam and was among the best lights tested. Its positive on/off switch is unmistakable in use. It may be leak-protected by a single O-ring but you never have to disturb it between battery changes. Scratch and crack-resistant ABS plastic makes it robust and needing little servicing. Careful use could see it last a very long time.

BURNTIME 4 hours
BRIGHTNESS 64
BATTERIES 4C
LIGHT SOURCE 5.5W Halogen
DEPTH RATING 150m
www.sea-sea.com

width=100%
width=100%MARES STROBE £30 (inc batteries)
More usable as a strobe than a true backup light, this also has three unfocused LED lamps at its other end, giving out the minimum amount of light. We couldnt get a reading on our sensitive light meter at 2m distance. It was quite fiddly to install the batteries. Single O-rings at each end are there to keep the water out, and we thought one of them looked a little slim for good reliability.

BURNTIME 12 hours
BRIGHTNESS No meter reading
BATTERIES 3AA
LIGHT SOURCE 3 LED
DEPTH RATING 40m
www.mares.com

width=100%
width=100%IKELITE PCLite £33 (inc batteries)
The bigger brother of some similar Ikelite lamps, it produced plenty of light in a rather patchy beam. In common with the others, it is switched on by means of a simple mechanical switch. It was relatively easy to slot in the bigger batteries, and we liked the way the O-ring was not subjected to any twisting motion when closing the battery compartment. Its an old design but it still does the job successfully.

BURNTIME 4 hours
BRIGHTNESS 32
BATTERIES 4C
LIGHT SOURCE Halogen
DEPTH RATING 90m
www.oceanicuk.com

width=100%
width=100%S-SUN HEADLAMP £35 (inc batteries)
A head-mounted light that can also be used on the wrist or shoulder, it has three operating modes that are selected sequentially by a single push-button. It didnt look too well-protected against flooding, with its one very skinny O-ring. Light output was quite poor, because the clustered LEDs were not well focused. It was more Dim Sum than S-Sun!

BURNTIME 12-24 hours
BRIGHTNESS 1.5
BATTERIES 2AA
LIGHT SOURCE 5 LED
DEPTH RATING 50m
www.wetbest.co.uk

width=100%
width=100%SEAC SUB SHOT £39 (Batteries extra)
We found this a very useful little back-up that produces lots of light from its big cluster of batteries. It was easily the brightest of the lamps tested. The mechanical switch is positive to use and a separate chassis for the batteries makes their installation easy. Double O-rings keep it watertight. It promised to be very reliable, but was a little heavy in the water due to the battery weight. It is made from ABS plastic.

BURNTIME 4 hours
BRIGHTNESS 96
BATTERIES 8AA
LIGHT SOURCE 6W Halogen
DEPTH RATING 100m
www.beaversports.co.uk

width=100%
width=100%INTOVA £40 (inc batteries)
Similar to the highly regarded original Aquastar, this is a very tough little aluminium-made lamp with double-O-ring protection plus a gasket, and has no through-body connections to leak because of its magnetic reed-switch. It produced a useful amount of light in a well-focused beam, and is easily stashed away. This manufacturer has no proven track record, but this was one of our favourites.

BURNTIME .5 hours
BRIGHTNESS 6
BATTERIES CR123A
LIGHT SOURCE ne high-output 3W LED
DEPTH RATING 25m
www.intova.net

width=100%
width=100%MARES TWIN BEAM £40 (inc batteries)
We unscrewed the light-sabre beacon section from this 2-in-1 device to convert it to a little back-up torch. Its made of heavy-duty anodised aluminium and has bags of shop-counter appeal, but its light output was little more than good enough to read a gauge as a last resort. Keep it as a nice-looking beacon, but dont expect much more. Frankly, its not up to the task of being a back-up light.

BURNTIME n/a
BRIGHTNESS 2
BATTERIES 1 CR123A
LIGHT SOURCE Single LED
DEPTH RATING 50m
www.mares.com

width=100%
width=100%LENSER FROGMAN LED £45 (inc batteries)
This neat little lamp uses hi-tech electronics to squeeze more light from its LED than you would think possible. The maker claims it to be 25 times brighter than normal, and we believe it. Early versions proved difficult to turn on at depth but this model has a new mechanical switch. It is solidly built in ABS, and 24-carat gold electrical contacts neatly avoid the corrosion common in marine environments. It should last well.

BURNTIME 20 hours plus
BRIGHTNESS 24
BATTERIES 4AA
LIGHT SOURCE One high-output 1.5W Cree LED
DEPTH RATING 60m
www.alphad.org

width=100%
width=100%TEK-TITE EXPEDITION LS4 £45
As is often is the case, the twist-on/twist-off function is the weak point of this lamp, but otherwise it gave a useful and even beam of light from its well-focused Luxeon Star LED. It will be a little long for some BC pockets, but short enough for most wallets. The long burntime means that you should always have enough to get you to the surface and see you through the night if your dive-boat abandons you.

BURNTIME 15 hours
BRIGHTNESS 8
BATTERIES 3C
LIGHT SOURCE High-output LED
DEPTH RATING 150m
www.tek-tite.com

width=100%
width=100%PRINCETON TEC TORRENT LED £47 (inc batteries)
We felt that this tough-looking plastic lamp would be very robust, even with hard use. A rubber shroud protects it from knocks. Its long burntime comes at the expense of lower light output than you would expect. The burntime depends on the type of batteries installed in the convenient internal chassis. We used conventional alkaline ones but it will run at the same brightness on only four batteries for half the burntime.

BURNTIME 4.5 hours (Alkaline)
BRIGHTNESS 8
BATTERIES 8AA
LIGHT SOURCE Single high-output LED
DEPTH RATING 100m
www.princetontec.com

width=100%
width=100%AQUATEC AQUA STAR 3 £49 (inc batteries)
Made in a lightweight grade of aluminium, this light is switched on by rotating the head to bear down on the battery connection. This can lead to switching on in your pocket at depth, or flooding by unscrewing too far. Only two slim O-rings protect it. The batteries sit in a separate chassis. The beam was useful but less bright than expected and not as good as its predecessor the Aqua Star (not reviewed here).

BURNTIME 6-8 hours
BRIGHTNESS 1
BATTERIES 6AA
LIGHT SOURCE Single 3W LED
DEPTH RATING 100m
www.wetbest.co.uk

width=100%
width=100%SCUBA PRO NOVA £50
This is an attractive little light made in aluminium. It looks very durable at first glance, and is small enough to be easily stowed away in a BC pocket. A question remains over the method of switching, because the push-button failed to operate properly for us at the pressure of depth. It tends to stick in either the on or off position. A single O-ring is intended to keep the water out.

BURNTIME 6-8 hours
BRIGHTNESS 6
BATTERIES 3AAA
LIGHT SOURCE 3W LED
DEPTH RATING 120m
www.scubapro.co.uk

width=100%
width=100%SALVO RAT JUNIOR £70 (inc batteries)
Double-O-ring-sealed but suffering from the same application defect as all lights with a screw-down shroud for switching, this strongly made Delrin lamp is only 12.5cm long, fits into the palm of your hand, and stows under a couple of elastic loops on a BC harness or in a pocket. There was precious little thread on the shroud, which begs the question: could a confused diver be trusted not to flood it

BURNTIME 6 hours
BRIGHTNESS 8
BATTERIES 2 CR123A
LIGHT SOURCE Single 2W LED
DEPTH RATING 150m
www.divingniknaks.com

width=100%
width=100%GREENFORCE DIAMOND PLUS £95 (inc batteries)
Designed to back up bigger Belgian-made GreenForce lamps, this one stows almost anywhere, and even has a holster for fitting to a harness strap. It is triple-O-ring-protected but is operated by screwing the head onto its contact, with consequent risk of flooding. It looks the part, is made to the same high standards in the same materials as its siblings and will run for hours, gradually reducing its light output after the first two.

BURNTIME 4-6 hours plus
BRIGHTNESS 8
BATTERIES 2 x CR123A
LIGHT SOURCE Single LED
DEPTH RATING 250m
www.lumb-bros-das.co.uk

width=100%
width=100%TEK-TITE EXPEDITION LS4 ALUMINIUM £99
Exactly the same in performance and function as the less expensive plastic LS4, this one is much more man for the job in that it is well-constructed, computer-machined from marine-grade aluminium. Double O-ring seals keep the water out. It will give five hours at full power, reducing its output for the next 10, and will appeal to those who like nice kit. Naturally, its heavier than the plastic version.

BURNTIME 15 hours
BRIGHTNESS 8
BATTERIES 3C
LIGHT SOURCE Single high-output LED
DEPTH RATING 600m-plus
www.tek-tite.com

width=100%
width=100%HALCYON MINI £105 (inc batteries)
Machined from Delrin to Halcyons high standards, this lamp is very durable. It has a well-designed handgrip, but with a screw-down shroud for switching with surprisingly little thread. This could lead to disaster with a careless diver. Less bright than some rivals, thats because the company puts reliability first when it comes to its philosophy of equipment redundancy, and under-runs the lamp.

BURNTIME 7 hours
BRIGHTNESS 6
BATTERIES 2C
LIGHT SOURCE Single LED
DEPTH RATING 150m
www.uk-halcyon.com

width=100%
width=100%SALVO RAT £105 (inc batteries)
The importer couldnt tell us what RAT stood for, but this double-O-ring-protected lamp is very well made. You would expect this at the price. Machined from one piece of Delrin, the RAT should last a lifetime if you can avoid twisting the front shroud the wrong way and flooding it while you are diving. It gave a well-focused, comfortable beam of light that was not as bright as some others but eminently useful.

BURNTIME 10 hours
BRIGHTNESS 14
BATTERIES 3C
LIGHT SOURCE Single 3W LED
DEPTH RATING 150m
www.divingniknaks.com

width=100%
width=100%HALCYON SCOUT £110 (inc batteries)
Strictly designed as a back-up light, this lamp, beautifully hewn from a solid rod of Delrin, has an under-run lamp to ensure that it is less likely to blow when switched on. This approach does mean that its brightness is less than it could be. Remarkably, a single O-ring and a screw-down shroud system for switching may introduce all the possible problems of flooding experienced by careless divers.

BURNTIME 5 hours
BRIGHTNESS 8
BATTERIES 3C
LIGHT SOURCE Single LED
DEPTH RATING 150m
www.uk-halcyon.com

width=100%
width=100%FA & MI POWER LED18 £125
Its a compact aluminium lamp with a magnetic reed-switch with no through-body connection, operated by a rotating collar. It looks robust, but the locking screw for the switch can easily go missing. The lamphead unscrews and is protected by a single O-ring, as is the separate battery compartment. Batteries are easily installed in a chassis connected by an internal short cable. We thought it usefully bright.

BURNTIME 18 hours
BRIGHTNESS 8
BATTERIES 4AA
LIGHT SOURCE Single high-output LED
DEPTH RATING 200m
www.cressi-sub.net

width=100%
width=100%GREENFORCE C2ETO £135 (inc batteries)
This seriously tough item in anodised aluminium and polyacetal has wacky styling. At 22cm long, it may be too long to stow easily. It is triple-O-ring-sealed but needs to be, as its switched on by screwing down the head. A switching routine allows you to select one of three degrees of brightness or a strobe setting, but we doubt whether anyone befuddled at depth could fathom it out. A non-dimmable version costs 120.

BURNTIME 7.5 hours
BRIGHTNESS 6
BATTERIES 2C
LIGHT SOURCE Single high-output LED
DEPTH RATING 250m
www.lumb-bros-das.co.uk

width=100%
width=100%COLTRI SUB EV0 50 £247
With its handle removed, this aluminium-made lamp is just small enough to qualify as a stowable back-up light. An easy-to-use rotating collar operates a magnetic reed-switch to turn it on and off. Batteries were easily installed on the fixed chassis. Two O-rings keep the water out. Overall, its a nicely made bit of kit and very even. It was one of the most satisfying lamps - but then it should be at the price!

BURNTIME 3 hours
BRIGHTNESS 16
BATTERIES 8AA
LIGHT SOURCE 3 high-output LEDs
DEPTH RATING 100m-plus
www.smp-ltd.co.uk

width=100%