# Light output of a car's brake lights



## Bart (Aug 8, 2001)

*Light output of a car\'s brake lights*

I don't have the equipment or devices necessary to get the light output ratings for a car's brake lights (single bulb). I was wondering if someone could do that for me so I can have some numbers to compare with? Is it possible to get the luminous flux (lumens)?


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## Bart (Aug 12, 2001)

*Re: Light output of a car\'s brake lights*

OK never mind... I give up


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## SCOTT THE BADGER (Aug 12, 2001)

*Re: Light output of a car\'s brake lights*

I think they run about 50 candlepower. I'm afraid I don't know the lumens.


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## Unicorn (Aug 12, 2001)

*Re: Light output of a car\'s brake lights*

Check both the packaging that the bulbs come in (check different brands and different stores, different brands might have the output listed), adn also the manufacturers catalogs at various auto parts stores.


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## Bart (Aug 12, 2001)

*Re: Light output of a car\'s brake lights*

scott, thanx... that may sound right. I do know that it has to be a certain rating for I think 45 degrees.

unicorn, I remember looking on a couple brands' packages but I've never found that kind of info... it's usually rated in watts, which I don't understand why because that's just the power used. a 55 watt halogen will be brighter than a standard 55 watt bulb, right? anyways, I'll try looking at some more brands.


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## PeLu (Aug 13, 2001)

*Re: Light output of a car\'s brake lights*

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Bart:
*I don't have the equipment or devices necessary to get the light output ratings for a car's brake lights. Is it possible to get the luminous flux (lumens)?*<HR></BLOCKQUOTE>

Here in Europe they use to have 20W, beeing 'normal' incandescent lights at max. 10lm/W (or a little less) giving some 200lm. Reflector and red lens will reduce it to some 50-70lm (my estimation).


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## Bart (Aug 13, 2001)

*Re: Light output of a car\'s brake lights*

OK, I finally found a website that was talking about a bulb upgrade from 1157 to 2357 for a motorcycle and they had the info on lumens and candela. 400 lumens for brake light and I think 32 candela. That's without secondary optics and I forgot that since the red lens blocks out all the other colors, you would lose a significant amount of luminous flux. Thanks people for your help. My LED brake lights with partial tail-light tint is 6 lumens X 27 LEDs...so, 162 lumens at 70 degrees viewing angle minus some luminous flux because of the fact that I'm not running them at their max ratings and because of the partial tint... and they're almost as bright as normal brake lights. I was trying to figure out how 400 lumens wouldn't be that much brighter than less than 162 lumens at the same viewing range (approx 70 degrees)... now it would make sense since the LEDs devote all of their light emitted energy to one dominant wavelength.


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