Quote Originally Posted by David88vert View Post
False. I have personally tested this. Take an old round lense (very common on older cars, and bikes), and put a factory HID in it (from a Lexus, Nissan, etc.). The light out put is significantly higher, and for a much farther distance (more that 3x as far than the best Sylvania, Philllips, or Hella bulbs). The issue is that it is unfocused, and scatters everywhere, blinding other drivers. Look at an S2000's headlights. Notice how they intentionally introduce an artifical top line to the light output. That is to reduce the light going towards other drivers.
HIDs produce a much larger amount of light, but need a controlling limiter to focus it where it is needed.
This is not false. How did you test this? I tested this with a 8 million dollar light tunnel in Germany with light metering equipment. I have seen and taken so many isolux readings that it would make your head spin. There is no parobolic or free form reflector on the planet that Meets SAE requirements with both an HID and Halogen lightsource. It's simply not possible. I use the SAE requirements becuase this is the industry standard of lighting. It's not necessarily/only a standard of what's legal, but more importantly what is needed to see at various speeds. The reflectors between the two light sources are 100% different, even on a non-complaint off-road or motorsports light. If it were this simple, Companies like Hella, Bosch, Valeo, Magnetti Marelli, Guide, etc. would be utilizing the same reflectors for both, and not spending billions on retooling for new reflectors.

If you see the output of a 7" Round Parabolic SAE Headlamp with an H4 compared to the same lamp with an HID kit on an isolux chart, you would understand. Although it appears brighter to the naked eye, its not even close. The focal points are completely different between H4 and the capsule. I have seen halogen H4 bulbs fail QC tests becuase the filiment is .012mm off. This little trivial amount can put the light everywhere but where it is needed. HID kits can be as much as 15mm off in multiple directions at the same time.

Here is some good reading on the topic from my friend Daniel Stern. It might explain the depate a little better.

http://dsl.torque.net/images/DSL_8885.pdf