The head torch is the bit of kit most walkers carry and fewest look at. It lives in the lid pocket, comes out once a season and is expected to work. In summer that rarely matters. From October on it matters a lot, because the gap between a late finish and a descent in the dark shrinks to an hour or less, and a slow group, a navigation error or a turned ankle uses that hour up.
Two separate questions. First, will your torch light the ground well enough, for long enough, in the cold? Second, was the day planned around the daylight actually available? A good torch backs up the second; it doesn’t replace it.
What the numbers on the box mean
Most reputable head torches are rated to the ANSI/PLATO FL1 standard, which defines how a few figures are measured. Knowing what each describes, and leaves out, prevents most bad buys.
- Light output (lumens). Total light emitted, measured 30 seconds after switch-on. Says nothing about how it’s spread, so two torches with the same figure can look very different on a path.
- Beam distance (meters). Where the beam falls to 0.25 lux, roughly full moonlight. It’s how far the light reaches, not how far you can see useful detail.
- Run time (hours). Time until output drops to 10% of the starting figure. That’s a long way down, so a torch rated for many hours on high may spend much of that time at a fraction of its brightness.
- Peak beam intensity (candela). How concentrated the brightest part is. High means a tight, far-reaching spot.
- Impact and water resistance. The drop height it survived, and an IP rating. IPX4 means splash-proof from any direction, enough for rain; IPX7 and IPX8 mean immersion.
Read output and run time together, setting by setting, not the headline lumens alone. A real example: Petzl’s Actik Core claims 625 lumens on max, but only for 2 hours; at 100 lumens it runs 7 hours and at 7 lumens 100 hours (petzl.com, Oct 2026). It weighs 88 g, is IPX4 and lists at $87.95. The 625 sells it; the 100-lumen line is the one you’ll walk on.
Regulated and unregulated output
The other figure that matters is often not printed: whether output is regulated. A regulated torch holds steady brightness for most of the battery life, then steps down, sometimes suddenly, to a low reserve. An unregulated torch starts bright and fades steadily.
Neither is wrong, but they need different habits. Regulated gives consistent light and little warning before the drop, so carry spares or know your remaining capacity. Unregulated warns you by dimming, but the light after a few hours may be far dimmer than what you tested at home.
Many current torches also have a reactive mode that adjusts brightness to what a sensor sees. It can stretch battery life a lot on a mixed path, at some cost to predictability.
Beam pattern for walking
At night, beam shape matters more than peak brightness. A narrow spot picks out a distant waymark or cairn but leaves the ground at your feet in shadow. A broad flood lights the immediate path evenly, which is what you want on rough ground, and is far less tiring to walk under for hours.
Most walking torches combine both: flood for the path, spot for looking ahead. A red light setting is worth having too. It keeps your night vision, dazzles others less at camp or in a bothy and uses very little power.
Modest output, used well, is often enough. A comfortable flood does for a clear path; higher settings are for route-finding, bad weather and descents where you need to see well ahead. Mist and falling snow bounce light back at you, and a lower, broader beam held lower on the body or in the hand can show more than a bright beam from your forehead.
Batteries and the cold
Cold cuts the capacity a battery can deliver, and how much depends on chemistry.
| Battery | In the cold | Notes | |-—|-—|-—| | Alkaline AA/AAA | Loses a large share of capacity below freezing | Cheap, everywhere; leaks if left in a torch for months | | Lithium primary | Copes far better: Energizer rates its Ultimate Lithium AA from −40°C to 60°C (−40°F to 140°F), with up to 25 years’ storage | The sensible default for an emergency light, if the manual allows them | | Rechargeable NiMH | Reasonable | Lower voltage can mean a dimmer beam in some unregulated torches | | Built-in lithium-ion | Loses capacity in the cold | Charges off a phone cable; when it’s flat, so is the torch, unless you carry a power bank or a hybrid torch (the Actik Core also takes AAAs) |
In the cold, keep the torch or its battery in an inside pocket until needed. Same for phones and GPS units, which our guide to offline maps and batteries covers. Pack spare batteries or a small second light; plenty of experienced walkers carry both.
Planning around the daylight
The torch is the backup. The plan is what keeps you off a steep descent in the dark.
- Check sunset and the end of civil twilight for the date and place. Usable light lasts a little past sunset, less in a glen, under trees or on a north-facing slope. On 21 December, Fort William’s sun rises at 08:55 and sets at 15:41 (timeanddate.com): under seven hours.
- Estimate route time honestly. Use your own pace on similar ground, not a guidebook time, then add breaks and a margin for the slowest in the group.
- Set a turnaround time that gets you to the hardest section, usually the steepest or most complex descent, in daylight. Stick to it.
- Know an escape route that’s easier to follow in the dark if the plan slips.
- Pack for a slower return. An extra warm layer matters because you’ll be moving slower by torchlight. Our piece on layering and insulation explains why stopping chills you so fast.
- Test the torch before leaving. Every mode, battery level, and the lock on so it doesn’t drain in the pack.
Before the season
- Replace or recharge batteries; check contacts for corrosion.
- Check the headband for stretch and the tilt hinge for wear.
- Learn the mode sequence, including how to get straight to the lowest and red settings.
- Confirm the lock-out works.
- Carry it every time, not just when you expect a late finish. Our guide to choosing gear by conditions treats short daylight as a condition that changes the kit list.
Quick answers
How many lumens for hillwalking? No single figure. A broad, even beam on a modest setting does most paths; higher output is for route-finding and poor visibility. Check run time at the settings you’ll actually use.
Rechargeable or batteries? Rechargeables are cheaper to run and handy for frequent use. For an emergency light living in a pack, one that takes lithium cells, or either, is more dependable.
Why does my torch dim after an hour? Either it’s unregulated and fading with the battery, or a regulated torch has stepped down to protect the battery or manage heat. The manual’s run-time chart shows which.
Should I carry a spare light? Yes. A small second torch covers a dead battery, a broken torch or a mate who forgot theirs, for very little weight.
