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Car CigLighter 12V LED Map Reading Light on 300mm gooseneck
How bright is the torch? That's a tricky question. It's bright enough to hurt your eyes if shone directly at them. A rating of X candlepower or lumens should mean the total light output is equivalent to X candles, but does not specify how focussed it is. A rating of X Lux or lumens per square metre means that at the centre of the beam the light you see is equivalent to the light on a square metre surface shed by X candles a metre away, but does not specify how broad the beam is. A rating of X foot candles means that at the centre of the beam the light you see is equivalent to the light on a square foot surface shed by X candles a foot away but does not specify how broad the beam is. A foot candle is about 10 Lux as the light is concentrated on a much smaller area. Really you need to know both the lumens and the lux, or else one of them and the angle of the beam. LED torches tend to have a very narrow beam but it depends on the lens and the number of LEDs - one LED might have a spread of only 20 degrees, a 3 or 7 LED torch usually has the LED aimed fairly parallel so there is not much additional spread, although there will be some spillage spreadout by the lens.
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