Biolight Headlamp 750

Headlamps have a dirty secret. Those numbers attached to their names and displayed on their boxes? They are boasts of brightness, measures of maximum light output counted in lumens, but they don’t tell the whole story.

What the makers of these lights fail to mention is that headlamps hit those high beam levels for only a short period before dimming down.

Headlamps do this to conserve battery life and achieve longer run times. Now Biolite is shedding light on the situation, so to speak, with Constant Mode, a setting that allows you to halt the dimming and run at a stable brightness for an extended time.

The mode maxes out at 500 lumens — the full 750 is reserved for Burst Mode — which it can run for two hours before dropping into a fivelumen reserve state. Set it at 250 lumens, and you can squeeze four hours out of it.

By contrast, other lights might begin to dim as soon as 30 seconds after emitting their full brightness. Extending that luminosity isn’t easy.

“The biggest tricky thing is the thermals,” says Ryan Gist, director of engineering at Biolite. “You have to keep the LEDS and electronics cold but also get that heat off so it’s not going right into your forehead or near the battery.”

The breakthroughs in the 750 come in part from products Biolite designs for use in developing regions of Africa.

Constant Mode isn’t the only standout feature though. There’s also Run Forever Mode, which keeps the light on forever when wired to an external battery in a backpack. And there’s a rear light for visibility, ensuring this honest illuminator looks just about as good from the back as it does from the front.

Specs

Light Modes: Spot, flood, spot and flood, strobe, burst, red flood, rear red flood, rear red strobe

Waterproofing: IPX4 (guards against rain, but not submersion)

Battery: 3,000 mah Li-ion, Micro-usb rechargeable $100

The Headlamp 750’s Constant Mode allows you to halt the dimming and run at a stable brightness for an extended time.