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Buying an LED Torch: Headlamp Design Considerations to Help Guide Your Purchasing Decisions

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by Rick Dreher | 2003-11-18 03:00:00-07

Be sure to check our Gear Guide to LED Headlamps.


If your brain isn’t overwhelmed by all the variables in our primer on LED headlamps, it’s time to go shopping. Your first priority should be to define your needs, then come up with a list of headlamps (or handheld flashlights) that match them. Try to test them all before selecting. If you’re a fair-weather backpacker who hikes mostly in the summer, you might be able to get away with a button cell microlight such as the popular Photon II or III. Weighing mere grams, it will still provide enough light to rummage through your pack or stir a pot of food by, and can be modified to attach to a cap for hands-free use (use self-stick Velcro or a binder clip). However, if you’re caught on the trail after dark, only those with owl-like night vision will find it possible to navigate anything but boulevard-like trails using one.

For non-technical trail navigation, a photo cell headlamp such as the Black Diamond Ion or PrincetonTec Scout give a brighter beam and hands-free operation at a little more than an ounce or two.

One of the compact LED headlamps driven by three AAA batteries can be considered the next step up. The Petzl Tikka and Zipka series, the Black Diamond Moonlights, the Princeton Tec Aurora and similar lights are still lightweight, while giving plenty of light for non-technical nighttime navigation and in-camp chores, such as hanging a bearbag - tasks for which button cell lights are overmatched. Used prudently, a single set of batteries can last a season and the light, with batteries, only weighs about three ounces.

Bigger, brighter headlamps come in a vast array of configurations. If you’re a predawn climber, a nighttime explorer, or go on long hikes on short winter days, you’ll probably want a hybrid headlamp or a multi LED multi mode headlamp that puts out serious light for traveling and frugal (battery-saving) light for your time in camp. We’re in a transition period during which more-sophisticated and powerful voltage-regulated LED lamps (like the Photon Fusion) will likely displace incandescent and even hybrid headlamps as the backcountry standard.

Design Considerations

Headlamps vary in layout. Here are some design options to consider while shopping.

Straps: Headlamps have either a single, adjustable elastic headband or a band plus a top strap. Some straps are only large enough to fit around the head, while others can be sized to allow fitting on a helmet. The top strap helps stabilize the light and keeps it from slipping while you’re on the move, but some folks find them annoying. In response, some headlamps have a removable top strap - perhaps the best of both worlds.

The Battery Pack: The batteries sometimes are stored in front, inside the lamp unit itself, sometimes in a battery pack attached the back of the head connected by a cable, and sometimes kept in a remote battery pack that’s not part of the headlamp itself, also connected by a cable. Bulk, balance and battery warmth are all considerations when selecting which configuration. The simplest, smallest models have everything in the lamp unit. The Petzl Tikka, Petzl Zipka and Princeton Tec Aurora are all examples. These tend to be a bit front-heavy in use and, because they don’t have center straps, can slide down your forehead while you’re active. But they’re also the lightest and most compact available. Informal field observations lead us to believe that the batteries don’t stay as warm in these lamps as they do with back-mounted battery packs.

Back-mounted batteries are generally the standard configuration for larger, higher powered headlamps. With the weight divided fore and aft and with a center strap, the headlamp will tends to stay in place on your head. When it’s cold, you can keep the batteries warm by wearing the headlamp under a jacket hood, increasing their life. Some headlamps put as many as three AA batteries up front but use a combination headband and over the crown strap to solve the slippage problem.

Remote battery packs allow you to keep the batteries warm and out of the way inside your coat, pants pocket or backpack. Very large battery packs, such as those using multiple C-cells, are too heavy and too bulky to keep on your head. Routing the connecting cable so that you don’t snag it at an inopportune time can be a challenge, though.

The Lamp Head: Lamp heads vary in design: some can be aimed by changing their angle, while others are fixed. The aimable (pivoting) ones are quite handy. Incandescent lamp heads generally have adjustable beams, focusing from spot to flood; LED lamps have fixed focus (unless they have switchable LED arrays). An LED lamp head that sits too close to the head can create annoying glare, especially for glasses wearers, because stray light can hit glasses lenses or even the eyes. Compare, for example, the Princeton Tec Aurora with the Black Diamond Moonlight. The Moonlight places the LEDs farther from the forehead, reducing the possibility of stray light hitting the face. Some headlamps are waterproof while others are open to the elements. While intruding rain won’t necessarily spell ruin to an LED light, sweat or saltwater certainly may - plus there’s the possibility of switch failure.

Beam Pattern: As noted earlier, LEDs come prefocused, so the lamp maker controls beam pattern by selecting and arranging them in the headlamp. Hybrid lights, whether LED/LED or incandescent/LED generally switch between a bright narrow high beam and a floodlight style low beam. With incandescent high beams, the beam itself is usually adjustable. Simpler lights - single or multiple LED with no options - have non-adjustable patterns that range from a spot to a circle to an oval, depending on model and maker. Also note that the beam thrown by a white LED generally has some intensity and color variation. It’s common to see a blue or purple fringe around the center white pool of light. This can be annoying for activities like reading. Some multi LED lights use a combination of focused and wide beam LED in combination with a reflector to have a lighting pattern that has a bright central beam but also good peripheral illumination.

Switches: There are pushbuttons, slide switches and twist switches. Lights having multiple modes may have one switch that does everything, or two switches - one for power and one for mode selection. Ideally, a switch will be easy to reach and use in all conditions, waterproof and won’t accidentally switch on in your pack. In practice, most switches are compromises from this ideal. It’s difficult to test switches in the store with cold, gloved hands, but you should at least keep the possibility in mind when shopping. (Editor's Note: The true test of the usability of a winter torch? The ability to operate the switch while wearing mittens.)

How to Test? The best way to decide which light is right for you is to borrow several and try them out. Next best is to read comprehensive, sometimes amusing, and sophisticated reviews online. In-store testing helps, but has its limitations. First, the store is brightly lit and your eyes will be daylight adjusted. Second, you have no way of knowing the battery condition in the various lights. Even so, playing with them in person means you can test whether they fit well, see their beam patterns and decide whether you can easily operate their switches, at least at 75 degrees. Be sure to move your head and bounce up and down to find out whether they stay put.

When REI first opened Gear Nirvana - their Seattle flagship store on Yale Avenue - they had the perfect solution: an enclosed diorama for their bicycle headlights. You stood at a rail in this darkened room and pressed buttons to switch on the various lights, illuminating the display (which had bushes, rocks, critters, etc.). The lights were powered by transformers, so that you knew you were comparing them all at full power. Something similar would be fantastic for comparing flashlights and headlamps. Retailers?


"Buying an LED Torch: Headlamp Design Considerations to Help Guide Your Purchasing Decisions," by Rick Dreher. (ISSN 1537-0364)., 2003-11-18 03:00:00-07.


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LED Lights
Discussion of light-emitting diode (L.E.D.)-based flashlights and headlamps. The reader is referred to the following articles as basis for this discussion:
In addition, to provide context for the lightware that is currently available on the market, the reader is also referred to:
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Richard Sullivan
(richard.s) - MLife

Locale: Supernatural BC
Re: AAA battery choices on 01/11/2004 18:10:14 MST Print View

Happy New Year to all because...

Energizer Introduces World's First AAA Lithium Battery

ST. LOUIS, Jan. 7 /PRNewswire-FirstCall/ -- Energizer Holdings, Inc. (NYSE: ENR), today unveiled its Energizer(R) e2(R) Lithium AAA battery, adding to its exclusive line of lithium 1.5 volt cells. It also announced performance improvements to its AA lithium line, now lasting up to 7x longer in digital cameras.* These two announcements put Energizer at the forefront of round cell lithium technology. And better yet, they arm consumers with the world's longest-lasting AA* and AAA batteries in high-tech devices at a time when the use of digital cameras, electronic games, PDA's, audio players and other high- tech devices is exploding. (*Versus ordinary alkaline in proposed ANSI testing. Results may vary by camera.)

The new Energizer e2 Lithium AAA batteries are now the world's longest- lasting AAA batteries in high-tech devices providing more memories, more songs and more messaging than any other battery available. For the consumer, for example, that can mean 160 more hours of paging messages or 400 more flashes. The product is built on the lithium technology Energizer pioneered in 1992. Energizer remains the only battery manufacturer to harness the power of lithium in a 1.5 volt cell.

"As today's high-tech handhelds like digital cameras and MP3 players get faster computing chips and higher-speed digital processing, their thirst for battery power goes through the roof. Energizer recognizes this, and has been extremely aggressive in providing high performance batteries to meet these demands," says Corey Greenberg, NBC Today Show's Tech Editor.

According to ACNielsen Panel Data (June 2003), the dollar sales of lithium AA batteries grew 25 percent versus a year ago and is helping to drive growth in the battery category.

In addition to the power advantages, Energizer e2 Lithium batteries are lightweight, 33 percent lighter than an alkaline battery. They operate well in extreme temperatures. In conditions where alkaline batteries would fail, lithium continues to operate in temperatures ranging from -40 degrees F to 140 degrees F. The batteries have a 15-year shelf life. The Energizer e2 Lithium AA and AAA batteries come in recloseable packaging for convenient storage and travel. The new AAA battery will be available later in 2004 just in time for the holidays when picture taking is at its highest and shoppers are selecting high-tech gadgets.

Energizer, headquartered in St. Louis, Missouri, is one of the world's largest manufacturers of primary batteries and flashlights and a global leader in the dynamic business of providing portable power.

SOURCE Energizer Holdings, Inc. 01/07/2004

CONTACT: Jackie Burwitz, +1-314-985-2169, or Harriet Blickenstaff, +1-314-995-3939 x103, both for Energizer Holdings, Inc.

Edited by richard.s on 01/11/2004 19:02:19 MST.

Richard Sullivan
(richard.s) - MLife

Locale: Supernatural BC
Re: Aurora criticisms, etc. on 01/11/2004 18:21:37 MST Print View

Further to my previous post, I was able to speak with the manager of the retail store which I mentioned. He noted that he had returned about 75% of the Auroras they had sold, less than 1% of the Tikkas, and no Tikka Plus models.

Aurora problems included "just about everything":
-switch button falling off
-switch contact failure
-electronics failure
-housing failure (cracking)
-pivot failure
-internal corrosion (due to the sealed construction, corrosive battery off-gases cannot vent)

They are continuing to sell the PT Yukon and Pulsar.

Edited by richard.s on 01/11/2004 18:23:00 MST.

Ryan Jordan
(ryan) - BPL Staff - MLife

Locale: Greater Yellowstone
Re: Re: AAA battery choices on 01/11/2004 18:25:53 MST Print View

FYI: will be carrying the new AAA lithium cells as soon as they are released to us for distribution. Next week, we should also receive our first shipments of other lithium round cell batteries, including the AA lithiums already on the market, and for you Black Diamond Ion fans, the lithium L544 BP.

Richard Sullivan
(richard.s) - MLife

Locale: Supernatural BC
Re: Headlamp Failure Modes on 01/11/2004 20:36:35 MST Print View

Well you've pretty well nailed it!

When Tekna came out with it's revolutionary lights in the early 80's, I thought we might have finally arrived. Their designs featured a sealed! switchless! polycarbonate! housing with halogen! bulb options, and one unit with a lithium! battery. Wow! (These design elements are still common to this day.) Ultimately though I ended up throwing them all away. One reason was the sealed design did not vent the battery off-gases and the contact surfaces degraded. You could even smell the gases when you opened up the lithium-cell unit, the MicroLith. Tekna upgraded the springs from phosphor-bronze to nickel-plated PB, but this was not a total cure. The bulb mounts were low precision which added to the problems. And the whole circuit was dependent on a spring pushing on batteries pushing on a bulb with a lead (Pb) contact point. This whole experience clearly evidenced that low voltage circuits are very susceptible to degradation caused by small increases in circuit resistance due to poor contact.

Now 20 years hence from the first Tekna lights, we have a lot more reliability due to LEDs, nickel-plated contacts, weather-resistant housings which will vent battery gases (BD, Petzl), and independent mounting and contacts for the supply and load. But new failure modes include cables and multi-mode or power management electronics. And our age-old nemesis The Switch is still lurking and looking to cause trouble. I am however highly impressed with quality of the current BD switches. And if electronics modules can attain high-reliability, then the switch might no longer be a point-of-failure since ideally it will not carry any current.

I'd like to see manufacturers eliminate single-points-of-failure as much as possible. For example:
-use two cables from the battery pack to the lamp head
-independent switches for flood and nav modes
-implement a bypass switch around the electronics module and multi-mode switch(es) i.e. a crowbar or switch-of-last-resort

In the meantime, I'll be carrying two lights on all trips. For example if you need a nav light then a Matrix 2 and a Tikka have a combined weight which is approximately equal to the Yukon HL, but with no SPOFs! And if the primary light is a Tikka or an Ion, then the backup can be a Photon or Pulsar.

David Spellman
(dspellman) - F
Headlamps and Green lights on 04/22/2004 18:19:00 MDT Print View

While aircraft and navy ships have, for years, used red as an optimum interior light to prevent night blindness, it seems that green is the new color on the block (as noted in the above article). I'm seeing more pilot chart lights with both red and green LED's, and even some tri-color (white is the third) units with a white lockout to prevent it accidentally being turned on.

One more thing -- I have a problem with headlamps in that they're at once in the best and the worst spot for illuminating trail. While it's handy to have them on your head and pointing the same direction you're looking (and they keep your hands free for other things), their flat lighting perspective does absolutely nothing for giving you a good idea of the "texture" of the upcoming terrain. I've found that I "see" the trail a whole lot better if I take off the headlamp and hold it by my side or even away from my body. That gives upcoming terrain features a certain amount of crosslighting and depth. Anyone else tried that?

Arapiles .
(Arapiles) - M

Locale: Melbourne
Re: Re: Aurora criticisms, etc. on 05/27/2004 07:10:29 MDT Print View

I bought a Princeton Tec Aurora last year and it is probably the worst piece of gear I've ever used. Mine was replaced under warranty but I threw the replacement into a corner and don't use it.

Problems included:

- the pivot ...] coming loose so that the headlamp hung down and shone into my forehead; the only way to fix this is to carry a micro-screwdriver (I wrapped a rubber band around it until I got home). Petzl's ratchet is a much better design;
- the rubber cover on the switch coming off in the pocket of my day pack, I got the cover back on and then realised that there was a tiny spacer (less than a centimetre long) between the actual switch (buried in the body of the light) and the rubber cover - this took ages to find, even though I knew it was somewhere in the back pocket of my day pack; an appalling, cheap and stupid piece of design;
- the light is advertised as water-proof - not water resistant, water-proof: I stuck it under a running tap and it immediately stopped working. I then spent several minutes cleaning and drying this "water-proof" light;
- the brightness dropped off spectacularly quickly: I have a number of torches and head-lamps and this was the worst I've seen.

The local importer replaced the light quickly once I complained but the point is that this light was out there, on sale, with a number of very serious design flaws. Yes, they addressed the flaws eventually - but not before I spent my hard-earned cash on one. Given the above, and the rock-solid reliability of Petzl torches you can imagine my surprise that the Aurora won your award as the best headlight out there.

P.S. you need to reset your "profanity detector" so it doesn't object to normal technical words

Edited by Arapiles on 05/27/2004 07:12:45 MDT.

Kevin Sawchuk
(ksawchuk) - BPL Staff - MLife

Locale: Northern California
Re: Headlamps and Green lights on 09/08/2004 17:35:04 MDT Print View

Please see comments on my 12/1 posting and Gary Lewis'12/16 posting about holding headlamps in hand while hiking/running. Yes it works much better.

Jeremy Best
(xtrem3djer) - F
Why these big lights? on 09/10/2004 22:04:58 MDT Print View

It seems no surprise that most people have overweight packs, because they can't give up the kitchen sink!
I carry two Photon II white led's that combined weigh 2/5 oz., and have never had a problem. Give up the straps, the tiny bit of convenience and save you back! If you do this, You will make it to your next destination before sun down and will not need to walk with a light. If you stick a piece of velcro to the light and then to your beany it becomes hands free!
Shoot, carry 5 Proton II's and you will still be lighter than those 5,6,7 oz. head lamps!

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
Battery Choices - single AAA on 10/09/2004 02:56:13 MDT Print View

The reason many headlights use 3 * AAA is to get enough volts to power a white LED, which needs between 3.0 and 3.6 volts.
I use a single AA or AAA battery and a micro switch-mode power converter (a few grams). I find about 50 mW of power is enough around the tent. A single AA lasted eight weeks continuous this way.
Roger Caffin

Mike Storesund
(mikes) - F
LED Choices on 01/17/2005 23:23:05 MST Print View

I really like the Petzl TacTikka with 3 ‘AAA’ Eveready Lithium batteries (2.3 oz. total). It has a red lens, so night vision is not impacted, that can be flipped down to offer white light when needed.

I also carry the Princeton Tech Eclipse (.4 oz.) as a backup. This 5-position light comes with both a hat visor clip and small key ring clip which are interchangeable. I use the key ring clip to clip it to the drawstring on top of the backpack for ready use when looking for gear.

Now the Lithium triple ‘A’ batteries are readily available at Wal-Mart, Target, Walgreens, Best Buy, Circuit City and many others. I found Target or Wal-Mart offer a better buy than the specialty stores. They may be here, but I have not seen them here yet.

Kevin Shuster
(drshuster) - F

Locale: Northern Arizona Alpine
LED lights on 10/07/2008 23:50:07 MDT Print View

I used the Princeton TEC that uses 2 lithium CR123, for over a year. I recognize that this is a relatively heavy peice of gear BUT.. It seems all thorns need to be removed after dark, and fun reading happen in the middle of the night.

I have numberous items that use the Li CR123 and though expensive... they are relatively light for the amount of charge they store (charge density). So I carry a couple extra CR123 batteries to replenish one or more items that might get extra use.

I am in the process of re-evaluating all my gear with an eye toward weight saving but this headlight keeps making "the cut" trip after trip. Especially in winter months, having such reliable, adjustable, infalable light... means something to me in the way of problem solving.