![]() A very white flashlight lamp will be rated around 3200 K.* Color temperature is expressed in degrees on the Kelvin scale. If two equally intense light sources differ in color temperature, the eye will perceive the whiter source (higher color temperature) to be brighter than the more yellow one. Another important factor besides absolute intensity is the whiteness (technically the Color Temperature) of the light source. Since the Total Output system does not take into account the focusing efficiency of the reflector, there is no way to convert between peak beam candlepower and lumens.Īdditionally, all light rating systems depend on the perception of the human eye and are therefore subjective. Typical values of beam candlepower will run into the tens of thousands for powerful rechargeable flashlights. For example, a flashlight of 20,000 beam candlepower would project, within its “hot spot,” the same amount of light on a wall as would a bare lamp of 20,000 candela at the same distance. The focused spot of light has the same intensity that a bare source of unfocused light of the same candlepower would produce on the same area from the same distance. It is a function of both the output of the lamp and the efficiency of the reflector. Peak Beam Intensity (Candlepower) is a measure of the brightest spot in the focused beam. For example, the 20 watt lamp used in the SL-35X is rated at 450 lumens or 35.8 Mean Spherical Candela. Multiply candela by 12.57 to convert to lumens. It is almost solely a function of the lamp, and for practical purposes is equal to the lamp output which lamp manufacturers rate in Mean Spherical Candela (Sometimes called Mean Spherical Candlepower which is not the same as peak beam intensity), or in lumens. This is a measure of the entire light output of the flashlight regardless of beam focus. Total Luminous Output may be expressed in candela or in lumens. There are two basic methods used by various flashlight manufacturers to rate the light output of their products. The Candela is also sometimes called candlepower, and is similar to an older unit, the candle, which was based upon an actual candle of specified dimensions and construction. The longer answer for candlepower compared to lumens:**Īll light measurements can be traced back to the Candela, which is the unit of luminous intensity. You certainly would not want to go on a walk in the woods at night with a laser pointer. ![]() Lasers have a very high candlepower because the light is focused into a single point, but it would have a very low lumen value because it does not give off a substantial amount light. A good example demonstrating the difference between lumens and candlepower is the laser. ![]() candlepower:Ĭandlepower is a measure of the brightest part of the beam of a flashlight whereas lumens is a measure of the total amount of light put out by a flashlight. Conversely, if you plan to do a lot of up-close work or need to evenly illuminate a space, you’ll want to stick to a lower candela rating.We get this question all the time: what’s the difference between lumens and candlepower? If you’re shopping for a flashlight to cut through fog and smoke or want a very hot center to your beam, you’ll want to pick a flashlight with a high candela rating. Although the reflector shape and size will also have an effect on throw distance, a higher candela rating tends to be indicative of a longer throw beam since the more intense light can be seen at greater distances. ![]() This measurement comes into play when looking for flashlights with long throw distance. By understanding candelas (cd), we can get a good idea of whether or not our flashlight will have a “floody” or “focused” beam.Īccording to Wikipedia, it is called such because 1 candela is approximately equivalent to the output from a candle, candelas measure the intensity of light in a single direction. While lumens are a good understanding of the total output of a flashlight, it doesn’t help us understand how intense or focused our flashlight might be. ![]()
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