What is a long Runtime Headlamp?

Other Types of Lights LED Headlamps
1

I’m looking for a new headlamp for caving. My main criteria is the longest possible runtime in the 100-200 lumen range. What emitter and driver combination would provide the longest stable output?

Preferred but not required: 18650 battery, ~ 4000k ~ 4500k tint, no greenish tints, able to have brief bursts of turbo (30 secs or less)

Thanks for suggestions!

2

Acebeam H30, 23.7hours at 120 lumen

3

For caving I suspect you want something with a little bit more intensity/throw.
I would recommend you look at the Zebralight H600w MkIV.

A larger XHP70 LED is techincally more efficient, but the difference will be marginal at 100-200 lumen range. By using the smaller XHP35 led in the Zebralight, you will get better intensity meanwhile on something like the Acebeam H30 it will be very floody and you will likely run it at a higher setting which will negate the added efficiency of the LED. It really depends on how far you want to illuminate. Zebralight H600 series is very popular amongst the caving community.