Lux, Lumens and beam distance
Lumens are units of luminous flux and represent the amount of light that a given headlamp produces. Lumens are suitable units of measure when comparing different lamps - the light with more lumens is stronger, it shines more. Lumens indicate the total amount of light, but do not say how narrow or wide the beam is. The lights that shine narrow may appear stronger than those with wide beam, although they may have fewer lumens (lower total luminous flux).
The light lumens can be roughly calculated from the data sheet of the LED chips, the current passing through, the losses caused by heating and the losses on the optics. Lumens can be accurately measured in an integrating sphere, which is expensive laboratory equipment. We use our own uncalibrated integration sphere to verify light parameters, we use the measured reference sample as a standard.
Number of lumens in our headlamps:
|Headlamp model||Max. lumens|
How many lumens do you need?
- camping: 5-10 lm
- walking: 10-25 lm
- jogging: 50-100 lm
- fast trail run: 200-400 lm
- orienteering run (night training): 400-800 lm
- orienteering run (night competition): 800-1600 lm
- night mtb ride: 400-800 lm
- night mtb race: 800-1600 lm
- mushing: 800-3200 lm
Lux is a unit of light intensity and determines the illumination at one particular measuring point - how much light hits that specific place. Luxes can be easily measured with a luxmeter, which is commonly used to measure a sufficient level of illumination of workspaces, desks in offices, etc.
Spot lights will have higher lux values than diffused lights. It does not automatically mean that the light with higher lux shines more!
1 lux is defined as the illumination of an area of 1m2, which is illuminated by 1 lumen.
Lux value decreases quadratically with increasing distance. Thus, for example, if the light has an intensity of 10,000 lux in 1 m, it will have an intensity of 2,500 lux in two meters, only 400 lux in 5 meters (= 10000 / (5 * 5)) and only 100 lux in 10 meters (= 10000 / (10 * 10)). At 100 meters then only 1 lux.
Some common lux values:
1 lux - moonlight
10 luxů - candle in the distance 30cm
400 luxů - work office
50000 luxů - sunny day
Light intensity of our LED headlamps in the distance 1m:
|Headlamp model||Intensity in 1m distance|
|Lucifer Z1, 20°||3850 lux|
|Lucifer S2X, 13°+20°||6200 lux|
|Lucifer M6, 13°+29°||8200 lux|
|Lucifer L, 13°+13°+13°+29°||19900 lux|
|Lucifer X, 6x13°||38000 lux|
Beam distance is defined as the distance at which the illumination intensity of the lamp decreases to 0.25 lux. This is approximately the intensity of the light produced by the full moon under clear skies. According to the ANSI / NEMA FL 1-2009 standard, the value is read between 30 - 120 seconds after the lamp is switched on.
Technically, its maximum illuminated distance. The real (usable) distance is lower.
Beam distances of our head torches:
|Headlamp model||Beam distance|
|Lucifer Z1, 20°||125m|
|Lucifer S2X, 13°+20°||159m|
|Lucifer M6, 13°+29°||182m|
|Lucifer L, 13°+13°+13°+29°||285m|
|Lucifer X, 6x13°||390m|