LooseCrew-JeffO: Nocturnal Running


Ramblings of an adventurous guy living in Denver and playing in the mountains.
For my trail adventures, visit my Trail Bum blog

Sunday, October 11, 2009

Nocturnal Running

This article about lighting for trail-runners has been worked on for years, and distributed to the Denver Trail Runners for several years, edited each year. The first copy was a 50/50 effort between Adam Feerst and myself.

Whether you’re running an ultra-event that goes through the night, or you just want to keep running through the short days of winter, you may be shopping for good lighting. Maybe you’re a gear-hog that already has plenty of different lights, but you may not be utilizing your gear optimally. During a race, there is no substitute for good lighting. If you’re running with insufficient light, you’ll probably either slow down for safety, or you’ll risk injury. If worried about weight, err on the side of too much weight/light than not enough. I've overheard too many elite runners complain that they had to slow down because they couldn't see. For these, a few more ounces of lighting would have more than paid for itself.

Some things to consider:
- Contrast gives you depth-perception
- Peripheral vision avoids vertigo and tunnel-vision
- Brightness gives you speed and confidence.
- Colored lenses
- Weight/bulk
- Battery life
- Cost

Contrast is created by having light away from your eyes where you can see some shadow to create depth perception. The more sources of light you have, from different angles, the better the contrasts will stand out. This is basic knowledge to any photographer wanting to make the subject stand-out.

Peripheral vision is aided by stray light. Reflectors try to block stray light and direct it forward for greater range. Since runners need the most effective light about 6 feet in front of them, reflectors are usually counter-productive. What's good for a camp light is not good for running a trail.
That is, unless you’re trying to follow reflective trail markers. In those cases, you’re not just trying to see for foot-placement, but also route-finding. Some headlamps have selective beams from long-range reflective to short-range dispersed.
Head lights leave your hands free and shine where you are looking. However, the light directly over your eyes can create glare, reducing contrast.
Hand lights can be easily directed and reduce glare. However, it takes practice to keep the light's direction from swinging while still using your arms.
Multiple lights can add depth-perception by countering shadows caused by a single light.

Brightness is determined by a combination of wattage, reflector, and the type of bulb you’re using. Incandescent bulbs are last century’s technology. They eat batteries and burn out, especially when dropped.
LEDs usually last forever. There are regular LEDs (less than 1 watt) and “super-bright” LEDs (more than 1 watt). The brighter LEDs are much better but use batteries faster.
There are, however, lights that utilize both LEDs and xenon or halogen. The battery-eating xenon/halogen is usually surrounded by a reflector that gives you a very bright projecting light. This gives you the best of both worlds. Depending on the unit model, you may have several switch settings that allow you to choose the brightness of light and longevity of your batteries. These hybrid gas/incandescent bulbs, used sparingly, are a luxury during moonless ultra-races through the night, especially races like the Hard Rock 100 where you’re above treeline looking for reflective markers a mile away.
Another option is to bring one Xenon or halogen flashlight with a button that can be depressed half-way for several seconds of reflector-controlled beam. This saves batteries and still allows superb long-distance lighting to pick out reflectors far away.

It’s better to have too much light than to have too little. Find the right level of brightness and weight, for the speeds and trails you want to run, and your own relative vision at night. Smooth paths may require no lights, while jagged, rocky trails with jutting tree roots require the max.
The closer your lighting is to your eyes – like a headlamp – the less the contrasts. This is because of the dancing shadows that give you a clue about how deep a hole is or how big a rock is. If the light is right next to your eyes, you’ll see no shadow. If the shadows are too dark, this may erode your confidence, making you slow down. Crisscrossing shadows give your eyes better perspectives.
Most headlamps can be converted to a waist or chest light.
If you’re only going to have one light, use it lower down for depth-perception. If you have a headlamp and a lower light, your headlamp should be the dimmer one to fill – but not obliterate – shadows created from your lower light(s).

Colored lenses severely diminish a bulb’s efficiency, but very bright-white light reduces the light-efficiency of your eyes (what’s called “night-vision”). Yellow, brown, and amber block blue light, which reduce haze and glare, and increase contrast making things clearer during speed sports. Red light is well-known for retaining night-vision.
Also consider weight and bulk. Some headlamps have the batteries integrated into the light, which is smaller and lighter with no wires, but tend to be front-heavy. Headlamps with separate battery packs are balanced, but are heavier overall and have wires which may end up getting mangled or worn-out.

Safety is another factor, mostly during training. Unfortunately many trail-runners do much of their training on roads. There are times you may not think you need any lighting, but consider there are times you want to be more visible to bikers and cars. Reflective clothing and a flashing tail-light can also be helpful. There's also the chance of meeting lions or bears on the trail. A flash of light in their eyes can blind them long enough to avoid an attack.

For short runs, rechargeable NiMH is great and saves plenty of money over the years.
Lithium is the other extreme, and is not rechargeable. It costs far more than any other battery but it runs longer too, and it’s immune to cold or going bad from sitting on the shelf. This may be a better choice for frigid winter runs. Lithium batteries have recently been found to damage LEDs from overheating. They are not recommended in moderate-to-hot weather. If you only have one LED bulb, only use them in the coldest environments where LEDs can’t reach critical temperatures, and you need the resilience of lithium. Overheated LEDs will become dimmer over time and will have to be replaced in order to return a flashlight to original brightness. However, if your light has multiple LEDs, then adding a little extra wattage won’t be able to damage them, even on warm nights. The more LEDs, the safer lithiums become.

Many lights are made from “aircraft-grade aluminum”, but this isn’t a good thing for runners. It’s heavier than plastic and far more durable than runners need. Some ads brag that you can drive over them with a tank or Humvee and they still work. I don’t anticipate any of my flashlights getting run over by anything, much less a military vehicle. Especially with regards ultra-running, every ounce counts.

Costs range from about $15 - $60. Headlamps tend to cost more than generic flashlights. The fancier features (LEDs+halogen reflector+4 switch settings) can send the price over $50.

When shopping, you’ll see ratings for candlepower and/or lumens. The term “watts” refers to power usage and doesn’t translate directly into brightness. Candlepower is a linear measurement equal to a birthday candle one foot away. A lumen is a square foot of light one foot away from the same candle.

Some packaging shows a silhouette of the beam. This can help you decide. Is the design for long range (better for hiking/camping) or for shorter range (better for runners)?

The most popular brands are Petzl, Black Diamond, Princeton Tec, Gerber, and Brinkman, but you may find others that are also very good.
One of my favorite flashlights is a 9-bulb Garrity that fits in the palm of my hand and runs lithium batteries without fear of degrading the bulbs. A lanyard is also a great feature on a hand-held light. The price is low enough to buy a couple for different drop-bags, while having an ideal weight/brightness ratio.
If I have to go with just one light, though, I'd choose a Tikka Plus. It probably has the best weight/brightness ratio available. I can wear it around my waist, or my head, or I can wrap the headband around my wrist and use it like a hand-held.

A partial list of stores and online dealers...
REI Outlet
Sierra Trading Post
Wilderness Exchange
Back Country
Adventure Racing Gear
Gear Zone
EMS Outlet
Bent Gate
Army/Navy Surplus, Kmart, Wal-Mart, Target, and at garage sales or Goodwill, ebay, amazon.

If you have any favorite places to shop, add a comment.

Lighting technology is taking leaps and bounds. Don't fixate on any specific model of light mentioned in this post. New models are coming out all the time, and new manufacturers, and old makes get new management (which overhaul the company). I think Petzl is clearly the best right now, but I reserve my loyalties because things are always changing.


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