Petzl’s newest headlamp, the Nao, is the first to feature reactive lighting. What this means is that the shape and intensity of the headlamp’s LED beam automatically change to better suit your lighting needs.
- Li-ion battery pack
- lockable on/off and mode selection switch
- light sensor
- wide-beam and focused-beam LEDs
- IPX4 water resistant to 30cm
- maximum output of 355 lumens
- minimum output of 7 lumens
- constant lighting outputs of 315 lumens or 8 lumens
- runtime of 1hr 20 min to 8 hrs
- lithium ion battery pack recharges via USB
How Reactive Lighting Works
The way we understand it, the Nao headlamp has a light sensor that compares reflected light intensity to the output intensity of the wide-beam of focused-beam LEDs. Since the beams spread with a known divergence angle, the relative intensity of reflected light, as measured by the integrated light sensor, allows the headlamp to roughly calculate the headlamp-object distance.
Petzl engineers have much experience designing quality headlamps, and so they have probably done extensive research to determine how much light output is optimal for different user needs.
This all makes a lot of sense. For close-up tasks and for reading instructions or charts, you don’t need a focused-beam LED at full-power; you need a wide diffuse light that’s easy on the eyes. For walking or running around in the dark or for medium-distance tasks, a wide medium-strength light is in order. For long-distance viewing, a focused beam will often be most effective.
From what we can tell, there are distinct benefits.
Going by this runtime chart, you can see that, with the headlamp set to constant lighting mode, the battery last for about 90-minutes at maximum output before the light output seriously degrades. With the headlamp set to reactive lighting mode, the battery lasts substantially longer, and the user saves time and effort from not having to adjust the settings as conditions and lighting needs change.
Of course, if you need the headlamp to operate at maximum output for prolonged periods, the reactive lighting mode will be much more of a hindrance than an advantage. That’s probably why Petzl offers the constant lighting override.
Since runtime under reactive lighting mode varies, here’s a detailed runtime chart that breaks the specs down a bit more.
We’re not quite sure how this works, but the Nao can be configured for customized lighting via free downloadable software. Users will be able to control the light intensity and duration based on activities, create up to 5 lighting profiles per mode, and register 4 activity profiles per headlamp.
Essentially, this all means that the Nao is somewhat programmable, somewhat like the not-yet-produced HexBright Flex flashlight is/was supposed to be.
MSRP is $175