On 7/6/2020 11:58 PM, Rolf Mantel wrote:

snip

Furthermore, the $15 StVZO light I linked was a *battery powered* StVZO
light which obviously gives the same power output independent of speed.
It has three power settings, "15 Lux/ 30 Lux / 60 Lux" (no idea how to
convert that to ANSI Lumens, or "fake raw Lumens" or whatever).

You can't convert directly since Lux and Lumens are measuring different
things. But for cycling, the best dynamo lights are around 100 lumens
per watt, so a 3 watt dynamo would be able to power about a 300 lumen
light. That mean that about 3 lumens per lux for a 100 lux light.

My best dynamo light is rated at around 200 lumens. That might be
sufficient for on a familiar street with street lighting, but certainly
not sufficient for an unlit multi-use path, especially some of the ones
around here where you often have to slow to 3MPH to go around the twists
and tight turns.

For street riding you generally want 500-600 lumens and for off-street
1200-1800 lumens.

I've never been into the "mega-lumens" philosophy and when I see these
3000 lumen lights for sale it's hard to understand the need unless
you're doing high speed off-road riding.