Originally Posted by ItsJustMe
I should amend my posting by saying that the perceived brightness is really hard to gauge. I think in reality the LED is really pretty weak. When that's all that's on at night it seems fairly bright. However, when I'm running with an LED, I get blinded by car headlights very fast. With my halogen, only for a couple of seconds as they approach, and with HID, not at all.
This has to be caused by the adabtability of the eye. When I photographed the LED based lights I have in my possession, I used the same camera settings for all of the lights. Your eye doesn't do this, it is constantly updating based on the information it receives, if the light dims, your pupil opens and vise versa. It would be worthless for comparison if I let the camera do this.
The biggest problem with the LEDs, is the lack of light spillage. There are some very good LED based lights out there, and they have the strengths and weaknesses like halogens (abysmal run times) and HIDs (very expensive). The can be made small and light, as well as bullet proof. That said, the 1 watt based lights do not put out the light that even a 10 watt halogen does, but would make a nice compliment light for helmet, if you have a bar light.