Luxeon 3W Star vs 2.5W Halogen Light

[jisozaki]

this is probably a really dumb question but is the "3W" designation on the 3W Luxeon star an actual power rating or is it the equivalent lighting?

I compared my MXDL flashlight with a 3W Luxeon star against a 2.5 W Halogen bulb from my Cateye bike light and the halogen bulb seems to be much brighter. The LED white is much whiter than the "yellow" halogen but the halogen light seems to do a much better job lighting up an area 20-30 feet away. both lights use 4 x AAA batteries of equal age. I thought the LED light would be much stronger since I thought LED's were much more efficient.

any light you can shed would be greatly appreciated (no pun intended).

 

[Steelwolf]

There are many factors that will affect your perception of how bright the light is. But let us first dispel a myth. THERE IS NO 3W LUXEON STAR.

The designation is LuxIII. It is essentially the LuxI die with a more robust wire and a redesigned thermal path that shows slightly less resistance to heat. This means that you can pump more power through it before it blows up.

Now, just because it can take more power, doesn't mean that it actually is. For example, the new L1 lights from Surefire use a LuxIII (for the better tint, the more robust wire and hence less internal resistance, the better heat dissipation from the die, etc.), but the booster circuit is designed to deliver 1W. So, you need to check how much power is actually getting to your LED.

Next, there is the question of beam spread. Most incandescent lights that I have used before tend to focus much of the beam in to a tight spot. Most LED lights I have seen don't have such a good focus. The beam is typically larger and more evenly spread. So by the time the beam reaches 20-30 feet, it could have spread out quite a bit, thus lighting up a bigger area than the incandescent, but perhaps not quite as brightly.

There are probably other, more arcane, factors, such as your eye's perception of different colours of light, and others more knowledgeable than myself will chime in, but perhaps you can check these 2 factors first.

 

[stormtrooper77]

I was going to post something about the brightest Lux vs a 4D Mag w/xenon bulb question, but I guess I could relate to this thread.

Questions like which is brighter overall, which has more throw, which is better close range, etc.?

 

[scudinc]

A 4D Mag produces a little over 60 lumens. A perfect U-bin Luxeon III could produce 113 lumens under ideal conditions. Realistically, it would make more like 70-80 lumens. The Luxeon would be better in everything but throw.