Re: Weisslicht LED Headlights?
Originally Posted by
SuperD500
In order to let the Lumens info be more than hearsay, you can look the specifications up for yourself at the respective manufacturer websites, or the many online comparison tests.
The difference between Lumens and Candlepower (Candela) is interesting, and I had to look it up.
A naked light bulb radiates the light it produces all around. This is measured in Lumens. No matter whether the light source is Halogen, Xenon or LED, Lumens is independent and it just expresses the amount of light produced.
The Headlight reflector and projector make it a narrow beam, in which the Lumens the light produces is radiated within a narrow cone. The brightest part of that beam is measured in Candlepower.
Candlepower is a measure of the brightest part of the beam of a light whereas Lumens is a measure of the total amount of light put out by a light.
A good example demonstrating the difference between Lumens and Candlepower is the laser. Lasers have a very high Candlepower because the light is focused into a single point, but it would have a very low Lumens value because it does not give off a substantial amount light.
So, what makes the Candlepower, is the amount of Lumens of the light used and the reflector and projector (lens) we have in our Crossfire’s Headlight. The Headlight is a fixed factor, cosidering you do not want to change that. Than the Candlepower depends on the Lumens only. Twice as much Lumens in the same Headlight means twice as much Candlepower in the resulting beam.
Candlepower does not matter when we talk Lumens because all that Lumens describes is the total amount of light produced. A light that produces 200 Lumens makes 5 times more light than a light that produces 40 Lumens. To give you a reference, an good old bulb of 60 Watt produces about 100 Lumens.
For this all to be true in a car’s headlight, the light emitting part of a bulb should be in the exact same spot, because the reflector and projector are designed to exactly match that spot. The new generation LED bulbs comply. The only problem we face here is the limited space in the Headlight.
Well said, what did your research do in finding the lumens specification was a function of how much light is produced based upon the amount of energy used? It's not just the light emitted, it's an energy conversion factor.
If we start with candlepower then we are on the same playing field but if you start with lumens the conversion to candlepower is skewed because of the energy used factor. That is why the LED rates higher lumens but isn't as bright isn't it?
Why would a Google search of "led headlight candlepower" in the quotes reveal no results with the quotes? How many LED spec pages show true candlepower?
I disagree with "Twice as much Lumens in the same Headlight means twice as much Candlepower in the resulting beam." Since lumens is total light output it could mean the LED is brighter but is the focus correct to where a driver needs it? This would be like your laser example. The H7 might be lower lumens but higher candlepower than an LED and produce more light where needed, on the road way in front of the car. This is why I really wish candlepower was the standard spec. Lumens can be deceiving.
Last edited by KDW4Him; Jul 3, 2016 at 04:51 PM.