A headlamp, as the name suggests, is a light source that can be worn on the head or hat, freeing hands, and used to illuminate.

Headlights are currently often used in trail running competitions. Whether short-distance 30-50 kilometers or long-distance events of about 50-100, they will be listed as mandatory equipment to carry. For ultra-long events longer than 100 kilometers, you need to bring at least two headlights and spare batteries. Almost every contestant has the experience of walking at night, and the importance of headlights is self-evident.

In the call-up post for outdoor activities, headlights are often listed as essential equipment. The road conditions in the mountainous area are complex, and it is often impossible to complete the plan according to the established time. Especially in winter, the days are short and the nights are long. It is also crucial to carry a headlamp with you.

Also essential in camping activities. Packing, cooking and even going to the toilet in the middle of the night, will be used.

In some extreme sports, the role of headlights is more obvious, such as high altitude, long-distance climbing and caving.

So how should you choose your first headlight? Let’s start with brightness.

1. Headlight brightness

Headlights must be “bright” first, and different activities have different requirements for brightness. Sometimes you can’t blindly think that brighter is better, because artificial light is more or less harmful to the eyes. Achieving the right brightness is enough. The unit of measure for brightness is “lumens”. The higher the lumen, the brighter the brightness.

If your first headlight is used for running races at night and for outdoor hiking, in sunny weather, it is recommended to use between 100 lumens and 500 lumens according to your eyesight and habits. If it is used for caving and deep into the dangerous environment of complete darkness, it is recommended to use more than 500 lumens. If the weather is bad and there is heavy fog at night, you need a headlight of at least 400 lumens to 800 lumens, and it is the same as driving. If possible, try to use yellow light, which will have stronger penetrating power and will not cause diffuse reflection.

And if it is used for camping or night fishing, do not use too bright headlights, 50 lumens to 100 lumens can be used. Because camping only needs to illuminate a small area in front of the eyes, chatting and cooking together will often illuminate people, and too bright light can damage the eyes. And night fishing is also very taboo to use a particularly bright spotlight, the fish will be scared away.

2. Headlight battery life

The battery life is mainly related to the power capacity used by the headlight. The usual power supply is divided into two types: replaceable and non-replaceable, and there are also dual power supplies. The non-replaceable power source is generally a lithium battery rechargeable headlight. Because the shape and structure of the battery are compact, the volume is relatively small and the weight is light.

Replaceable headlights generally use 5th, 7th or 18650 batteries. For ordinary 5th and 7th batteries, be sure to use reliable and authentic ones bought from regular channels, so as not to falsely standardize the power, nor will cause damage to the circuit.

This kind of headlight uses one less and four more, depending on different usage scenarios and needs. If you are not afraid of the trouble of changing the battery twice and pursue light weight, you can choose to use one battery. If you are afraid of the trouble of changing the battery, but also pursue stability, you can choose a four-cell battery. Of course, spare batteries must also be brought in a set of four, and old and new batteries must not be mixed.

I used to be curious about what happens if the batteries are mixed, and now I tell you from my experience that if there are four batteries, three are new and the other is old. But if it can’t last for 5 minutes at most, the brightness will drop rapidly, and it will go out within 10 minutes. After taking it out and then adjusting it, it will continue in this cycle, and it will turn off after a while, and it will become impatient after a few times. Therefore, it is recommended to use a tester to directly eliminate the battery that is too low.

The 18650 battery is also a kind of battery, the working current is relatively more stable, 18 represents the diameter, 65 is the height, the capacity of this battery is usually very large, basically more than 3000mAh, one top three, so many are known for battery life and brightness The headlights are willing to use this 18650 battery. The disadvantage is that it is large, heavy and slightly expensive, so it should be used with caution in low temperature environments.

For most outdoor lighting products (using LED lamp beads), usually 300mAh power can maintain 100 lumens brightness for 1 hour, that is, if your headlight is 100 lumens and uses a 3000mAh battery, then the probability can be bright for 10 hours . For domestic ordinary Shuanglu and Nanfu alkaline batteries, the capacity of No. 5 is generally 1400-1600mAh, and the capacity of the smaller No. 7 is 700-900mAh. When purchasing, pay attention to the production date, try to use new instead of old, to ensure the best Good efficiency to power headlights.

In addition, the headlight should be selected as far as possible with a constant current circuit, so that the brightness can be kept unchanged within a certain period of time. The cost of the linear constant current circuit is relatively low, the brightness of the headlight will be unstable, and the brightness will gradually decrease over time. We often encounter a situation when using headlights with constant current circuits. If the nominal battery life is 8 hours, the brightness of the headlights will drop significantly at 7.5 hours. At this time, we should prepare to replace the battery. After a few minutes, the headlights will go out. At this time, if the power is turned off in advance, the headlights cannot be turned on without changing the battery. This is not caused by low temperature, but a characteristic of constant current circuits. If it is a linear constant current circuit, it will obviously feel that the brightness will be getting lower and lower, rather than decreasing all at once.

3. Headlight range

The range of the headlight is commonly known as how far it can shine, that is, the light intensity, and its unit is candela (cd).

200 candela has a range of about 28 meters, 1000 candela has a range of 63 meters, and 4000 candela has a range of 126 meters.

200 to 1000 candela is enough for ordinary outdoor activities, while 1000 to 3000 candela is required for long-distance hiking and cross-country races, and 4000 candela products can be considered for cycling. For high-altitude mountaineering, caving and other activities, products of 3,000 to 10,000 candela can be considered. For special activities such as military police, search and rescue, and large-scale team travel, high-intensity headlights of more than 10,000 candela can be considered.

Some people say that when the weather is good and the air is clear, I can see the firelight several kilometers away. Is the light intensity of the firelight so strong that it can kill the headlight? It is not actually converted in this way. The farthest distance reached by the range of the headlight is actually based on the full moon and moonlight.

4. Headlight color temperature

Color temperature is a piece of information that we often ignore, thinking that the headlights are bright enough and far enough. As everyone knows, there are many kinds of light. Different color temperatures also affect our vision.

As can be seen from the above figure, the closer to red, the lower the color temperature of light, and the closer to blue, the higher the color temperature.

The color temperature used for headlights is mainly concentrated in 4000-8000K, which is a more comfortable range visually. The warm white of the spotlight is generally around 4000-5500K, while the bright white of the floodlight is around 5800-8000K.

Usually we need to adjust the gear, which actually includes the color temperature.

5. Headlight weight

Some people are now very sensitive to the weight of their gear and can do “grams and counts”. At present, there is no particularly epoch-making product for headlights, which can make the weight stand out from the crowd. The weight of headlights is mainly concentrated in the shell and battery. Most manufacturers use engineering plastics and a small amount of aluminum alloy for the shell, and the battery has not yet ushered in a revolutionary breakthrough. The larger capacity must be heavier, and the lighter one must be sacrificed. The volume and capacity of a portion of the battery. Therefore, it is very difficult to find a headlight that is light, bright, and has a particularly long-lasting battery life.

It is also worth reminding that most brands indicate the weight in the product information, but it is not very clear. Some businesses play word games. Be sure to distinguish the total weight, the weight with the battery and the weight without the headband. The difference between these several, you can’t blindly see the light product and place an order. The weight of the headband and battery must not be ignored. If necessary, you can consult the official customer service.

6. Durability

Headlights are not disposable products. A good headlight can be used for at least ten years, so the durability is also worthy of attention, mainly in three aspects:

One is drop resistance. We cannot avoid bumping the headlight during use and transportation. If the shell material is too thin, it may be deformed and cracked after being dropped a few times. If the circuit board is not welded firmly, it may be directly powered off after several times of use, so purchasing products from major manufacturers has more quality assurance and can also be repaired.

The second is low temperature resistance. The nighttime temperature is often much lower than the daytime temperature, and laboratory tests are difficult to simulate extreme low temperature conditions, so some headlights will not work well in extremely cold environments (about -10°C). The root of this problem is mainly the battery. Under the same conditions, keeping the battery warm will effectively prolong the use time of the headlight. If the ambient temperature is expected to be very low, it is necessary to bring extra batteries. At this time, it will be embarrassing to use the rechargeable headlight, and the power bank may not work properly.

The third is corrosion resistance. If the circuit board is stored in a humid environment after a long time, it is easy to mold and grow hair. If the battery is not removed from the headlight in time, the battery leakage will also corrode the circuit board. But we usually seldom disassemble the headlight into eight pieces to check the waterproof process of the circuit board inside. This requires us to carefully maintain the headlight every time we use it up, take out the battery in time, and dry the wetted components as soon as possible.

7. Ease of use

Don’t underestimate the ease of use design of headlights, it is not easy to use it on the head.

In actual use, it will bring out many small details. For example, we often pay attention to the remaining power, adjust the illumination range, illumination angle and illumination brightness of the headlight at any time. In case of an emergency, the working mode of the headlight will be changed, the strobe or strobe mode will be used, the white light will be changed to yellow light, and even a red light will be issued for help. If you encounter a little bit of unsmoothness when operating with one hand, it will bring a lot of unnecessary trouble.

For the safety of night scenes, some headlight products can be bright not only in front of the body, but also designed with tail lights for collision avoidance behind, which is more practical for people who need to avoid vehicles on the road for a long time.

I have also encountered an extreme situation, that is, the switch key of the headlight power supply is accidentally touched in the bag, and the light leaks in vain without being aware of it, resulting in insufficient power when it should be used normally at night. This is all caused by the unreasonable design of the headlights, so be sure to test it repeatedly before purchasing.

8. Waterproof and dustproof

This indicator is the IPXX we often see, the first X represents (solid) dust resistance, and the second X represents (liquid) water resistance. IP68 represents the highest level in headlights.

Waterproof and dustproof mainly depends on the process and material of the sealing ring, which is very, very important. Some headlights have been used for a long time, and the sealing ring will be aging, causing water vapor and fog to enter the inside of the circuit board or the battery compartment when it rains or sweat, directly short-circuiting the headlight and scrapping it. More than 50% of the reworked products received by headlamp manufacturers every year are flooded.