Headlamps - making the right choice

Head lamps – making the right choice

Perhaps I’m giving my age away – but do you remember when all men wore the same thing to go hiking – Tesav rugby shorts, cotton T, red loop stitched socks & T5’s ? When it rained you pulled out your Drimac and got sweaty ! Then Goretex arrived, followed by Polarfleece and Pertex – and suddenly dressing for the hills became a more technical (and expensive) endeavour. Shortly there after the competition started – everyone & his pet dog started to make Polarfleece and the original morphed into Polartec – in different series 100, 200, 300. A plethora of waterproof “breathable” fabrics arrived – Ventex, Sympatex, X-Country DriClim etc.

Soon it became apparent that it wasn’t enough to recognise brands – one has to understand the underlying technology and, more especially, what function various fabrics are designed to perform so that you can choose the fabric best suited for your intended pursuit. With so many new technologies, brands, manufacturers and retailers popping up in the realm of technical outdoor clothing, consumers quickly learned to “get with the programme” or get burned with sub-performance or over price choices.

Headlamp technology has gone through similar technological changes and while most people have adapted to the complications in clothing choice – the shift in the manner in which consumers choose their headlamps (or personal lighting) has been much slower. Unfortunately most customers currently choose their personal lighting on the basis of :

1. Brand dominance

2. What their friend recommends – which is usually a circular self fulfilling prophecy.

The fact that the dominant brand is not keeping pace with developments in other brands seems to be excluded by “comfort zone” thinking. Simply put - the dominant brands in personal lighting don’t always offer the best performance or value for money. As a result it will benefit consumers to get a handle on the criteria used to compare different lighting products. This is particularly important since sooner or later most outdoors men / women find themselves in a situation where their choice in personal lighting makes the difference between a comfortable night or an epic (or worse).

So – what are the factors that should be considered when choosing a personal light ?
1. Performance :
a. Usable light – measured by Lumens & throw
b. Battery life
2. Economy
a. Battery choice
b. Price vs. After sales support
3. Durability :
a. Build quality
b. Water resistance
4. Design features :
a. Ergonomics
b. Function in the field

1. Performance:
Headlamp performance is measured in a number of ways. The most recent buzz word is “Lumens”. This is the amount of light put out by a light source – measured in Lux. While this measurement does give a general indication of a headlamp’s “power” – it does not give any idea of what the unit is actually capable, since it is the “captured” or “usable” light that is the real determinant of performance. Put another way, it is possible to use a huge amount of energy creating enough light to perform brain surgery, only to have it diffuse in a very short distance from the source because it is completely un-concentrated. The converse is equally true; a well constructed lens can throw a relatively small amount of light quite far while consuming very little energy. In short therefore, it is necessary to consider both the Lumen rating and the throw distance in order to get a good handle on the headlamp’s performance.

Generally you will pay for what you get. If your use is to see if the ‘wors is done well enough, it’s pretty pointless forking out R700 for a headlamp. On the other hand, if having completed climbing that big wall and are faced with scrambling and abseiling down 500m of cliff in the middle of the night – you most definitely do want a headlamp which will give you a 70m + beam for upwards of 10 hours or more and so parting with your hard earned shekels is easily justified.

2. Economy :
One of the great advances introduced by LED (light emitting diodes)headlamp technology is the duration of light that can be squeezed from a regular battery. Whereas my original Zoom gave me a mere 18 hours from a huge 4.8V battery, one is now able to extract up to 200hours of usable light from three 1.5V AA’s. However there is a balance between light “power” and battery durability.

It is quite possible to design circuits which will allow a lowly LED headlamp to burn the back of your retina – but they will chew the battery power in a couple of hours. Not much use when you are fighting your way down that mountain, eight hours from daylight. Unfortunately consumers can be so impressed with the headlamp’s output in the shop that they quickly commit to the purchase, only to realise that they have to keep on giving to keep the light burning – and at R40 per set of four AA’s, could have done better by spending an extra R100 on a light that gives better burn times.

It is also important to realise that when a headlamp claims a battery life to 200 hours – that is not 200 hours at it’s maximum brightness output. The output from most headlamps will follow a shallow concave curve, dropping off fairly quickly to begin with and then declining into nothingness over a longer period. The exception are lamps equipped with current regulation which allows the lamp to sip power for a longer period, at a lower output, after which the output drops much more dramatically.

In order to paint a more accurate picture for consumers, leading headlamp manufacturers including Black Diamond, Petzl & Princeton Tec have agreed on standard whereby this information can be communicated clearly. Burn times are now represented as beam distance at T0 (fresh batteries), T0.30hr and T10hr – in other words how far the beam throws when just turned on, after half an hour and after 10hours of burning.

An alternative approach is to provide the lumen output & throw that can be expected at the different battery durations e.g. 250hours at 2 Lumen and 10m. However always remember that at the brighter settings, the light output will follow a declining curve – i.e. if the lamp indicates 40m at 55 lumens on high for 50hours – that means that the batteries will last for 50hours on that setting; but you can be sure that you will not be able to see for 40m after 45 hours of continuous burn time. Be wary of headlamps that don’t provide this kind of information.

Not only does this information impact the amount of money you pour into batteries to keep your light working and the number of batteries you discard which are environmentally harmful, but it also determines how quickly you will be reduced to finding your way down that mountain with only 2m of light!

Given the magnitude of the impact of disposable batteries on the environment, a number of the leading manufacturers are turning their attention to re-chargeable units. These headlamps generally plug into the mains just as you would a cell phone and they make good economic sense if you use your headlamp regularly. However if you are to travel further afield and to remote destinations – make sure you can either re-charge in your vehicle or can substitute regular disposable batteries once your rechargeables run dry.

3. Durability :
This is usually a function of build quality and the degree to which the light is built to be waterproof. Most quality headlamps are built in a very strong polycarbonate which can be seriously abused. The robustness of the lamp is generally indicated by the duration of the manufacturer’s warrantee. Most of the quality manufacturers will give a 3 year warrantee, and while some will do more – the truth of the matter is that the technology is advancing at such a rapid pace that many folk will replace their lamp after 3 years anyway because the old one is no longer up to scratch.

Water ingress is probably the most common reason for headlamp failure. Having said that, most modern headlamps will burn underwater for a period with all their circuitry exposed. It’s not the short term exposure to moisture that does the damage. It’s usually only when batteries are left in a wet environment for a period of time, that they short out, corrode & burst, which in turn burns the head lamp circuitry and wiring.

So – if you’re an adventure racer or paddler and you expect to get your headlamp wet regularly, look for one which has an IPX7 (submergible to 1m) rating. If you’re a mountaineer and you have a lamp that has an IPX4 rating and you walk for a night in the rain – open it up and dry it our properly when you get to shelter.

4. Design features & weight:
Once you have decided on your shortlist based on the criteria discussed above, compare the features of the different lamps. The usefulness of various features is usually determined by the purpose for which you intend to use the lamp.

For instance the cradle-type rechargeable feature of the Black Diamond Sprinter may be very useful for the urban runner training after dark, but won’t be much use to the expeditionary mountaineer days from the nearest plug in point. Likewise the fact that the Black Diamond Wiz turns off on it’s own after two hours and requires a screw driver to access the battery pack, will be appreciated by parents of young children, but may annoy other users.

Look at the ratchet mechanism. The Princeton Tec Fuel / Remix series of lights makes use of a side mounted arm on which to swivel the headlamp. This ensure that no amount of head bounce will cause the lamp to droop downward.
Also examine access to the battery casing. There is little that will annoy one more than struggling to access the casing when the batteries are running flat – and breaking the cover or hinge in the process.

The switch mechanism is also worth checking. A number of people have complained to me about switches which are too small to operate with gloves on. It’s also annoying to have to always flick through 3 different modes to achieve the setting that you prefer to use. The new Black Diamond units have a dimming switch which allows almost infinite levels of adjustment by just hold the button for a period.

The number and size of the batteries required to power the headlamp will usually determine the weight of the unit, but construction materials can also have a significant effect. Trying to run with a block of lead on your forehead will not do your neck muscles any favours. So compare the weights of the various units – including batteries.

So in summary : here are your steps for choosing a good headlamp :

- Decide on the “worst case scenario” for which you are equipping yourself

- Decide on the level of immediate broad brightness vs. long distance throw that you require - compare the stats given on the packaging of the lamps you are considering.

- Toss up your “brightness” requirement with your battery duration - compare the stats provided on the packaging of the lamps you are considering

- Decide on your durability & waterproof requirement. Consider the benefits of paying more for a reputable brand which will offer a longer warrantee

- Decide on the features which make the headlamp most suitable for your purpose.