The Petzl NAO is the best headlamp I’ve ever worn. In the past I’ve used various models from Black Diamond, Petzl, and Fenix while camping and caving. Each one had it’s own quirks, but they all, at the end of the day, provided ample light in dark places. What the Petzl NAO does differently is provide a tremendous amount of light in an intelligent and usable manner that makes it easier to do things in the dark.
The stand out feature of the Petzl NAO is the reactive lighting. On top of the headlamp is a light meter that measures the amount of reflected light in order to adjust light output. When you, for example, need to read a map, it senses an increase in reflected light and simultaneously dims light output while switching from a spot-light to a more diffuse beam. This is all automated, and happens instantaneously. After wearing it for an evening, it became indispensable. It’s especially a boon when working with other cavers or campers because it automatically dims when looking at someone, preventing any unintentional blinding. The only downside I’ve read about is for bikers as the beams of an oncoming car can trigger the light to turn off (so bikers will want to turn this feature off).
Previous headlamps I’ve owned, especially those with battery packs, have been really uncomfortable after extended wear. The NAO, with it’s slightly smaller battery pack, only weighs 180 g, and has a really comfortable set of straps. I’ve worn it running and hiking and have found it to far comfier than the competition.
It also doesn’t hurt that the NAO produces an incredible amount of usable light. It’s rated at a respectable 355 lumens produced by two LEDs. Unlike other mono-LED lamps (like my Fenix), the two LEDs act in concert to create both diffuse light and a beam with a powerful throw. WIth that being said, there are many headlamps that can do this, and the feature that really sets the NAO apart is the auto-dimming.
The last feature worth noting is that the NAO features a USB-rechargeable Li-ion battery pack that is programmable with software provided by Petzl. The software allows you to tweak how the headlamp responds in different environments and activities. I designed a profile for camping which features an ultra-low power mode for reading in the tent, and a much brighter mode with greater throw for trail-running in the dark. While it is a bit gimmicky, the profiles work well in use. The 2300 maH battery pack can be switched out for two AAAs, but it can be a bit tricky and they don’t last very long. While I have not had any problem with the batteries, those going on longer expeditions may want to hold off until the Li-ion packs are a bit cheaper.
There’s no getting past the fact that the NAO is an expensive light at $175. But to me, and I expect to many others who spend a fair bit of time in the dark, the fact that it intelligently responds to my lighting needs makes it well worth the cost.