On Wed, 06 Dec 2017 13:51:55 +0700, John B wrote:

I've always thought that all the discussion about Lummins, luxes, and
whatever else, ignores what I suggest may be the most important fact,
the ambient light. In a situation where there is no light, where one
literally cannot see one's hand in front of their face, lighting a
match provides a truly amazing amount of visibility. I've also noticed
the reverse phenomena driving on roads with large overhead lighting.
Gee, can hardly see any light from the headlights.

I've noticed the same thing. I mentioned upthread using my B&M halogen
headlight on dusk-to-dawn brevets and PBP. I saw quite well with that
light, but most of those rides were far out on rural roads with very
little ambient light or light pollution. In town that light is washed
out on the road by street lights, car headlights, etc. Technically
the road is just as brightly illuminated by the lamp as in the
country, but the greater ambient light in town impairs night vision
by comparison to a very dark countryside. Thus the light seems less
effective. And since we're seeing with our eyeballs and not spot
meters, it is less effective in town. Perhaps the "Kleig light" fans
are riding primarily or exclusively in urban settings?

I've not taken the opportunity to due a rural night ride with my Schmidt
eDelux; in town it's less washed out than the halogen. I still use the
halogen on my commuter bike (ironically enough) with an old Sanyo BB
generator. What a nice, smooth low resistance design.

I just bought a Velological generator to try on one of my bikes; that's
waiting for the arrival of the eDelux II. The Velological wiring layout
puts a 12v 120W halogen bulb in the circuit to act as a thermistor and
bleed off voltage at high speeds (the generator itself has no voltage
regulation); not sure why that instead of using a zener diode. My
knowledge of electronics is deficient.