Oxford University Cave Club

LED's

Lev Bishop

During recent years, most OUCC expeditioners have settled on a semi-standardised lighting set-up comprising a carbide generator (usually a 300g Fisma) and headset (Petzl aceto) combined with an electric backup (often an oldham headset connected to a helmet-mounted 4.5v "flatpack" alkali battery). This system is very appropriate to the type of caving we undertake in the Picos, but apart from the details it is one that hasn't changed in many years. This year, due to the kind generosity of HDS systems, I was able to use an ActionLight, altogether a much more state-of-the-art lighting system. The model of light which I was using is the original All-In-One version, which is a single box that contains one 'D' sized lithium battery, 24 white LEDs, and the associated power-supply and switching electronics.

The light has three brightness settings, easily changed by a rotating knob. I found the medium setting provided ample light for most of the caving, resorting to the highest setting only for the large walking passages such as the London Underground. The lowest setting gave enough light for SRT and for sitting around whilst eating or waiting for other cavers. This, I think, is the big advantage of LEDs over ordinary incandescent bulbs; the ability to dim the light without losing efficiency means that it is possible, with a little willpower, to be very frugal with batteries without having to struggle with insufficient light for any task. The colour of the light was very white and I found it very pleasant to use, although it did occasionally appear to other cavers that there was a patch of daylight somewhere above them. It was quite soft and diffuse, rather more like a carbide than a typical electric. I carried a helmet-mounted 2xAA diving light for looking into the distance (and as a backup) but found I rarely needed it.

Overall, I was extremely pleased with the light. It provided a very easy light by which to cave. It was totally reliable and gave me no problems with loose connections or unexpected darkness whilst negotiating tricky moves. It was much more convenient than a carbide lamp, requiring no fettling, filling with water, or any of the other attention-seeking antics that you get with carbide, nor did I have a generator on my waist and a tube on my back to catch and hang me up at inconvenient times. The biggest advantage, however, was that I didn't need to carry spare carbide with me. When others were lugging bottles full of rocks up the mountains and down the caves, I was able to carry a single 85g spare battery with me, even on camping trips. I am now of the opinion that anyone thinking of buying his first lighting set-up for expedition would be well advised to purchase a lamp like mine, for all of these reasons, as well as the fact that the "learning curve" is much lower than for carbide, and that by getting an LED system you avoid the need to have separate carbide set-up for expeditions and electric lamp for use in the UK.