Originally Posted by
Richard Cranium
Gee-sus even you analogy is flawed. And I won't argue with twisted logic.
Mr. Cranium, I have a BFA in Sculpture and went on to grad school for related studies.
I have quite a bit of experience dealing with light, perception of space, vision, how the eye digests it, and how to capture form using it.
Note that I stated I prefer my light, an Edeluxe, mounted somewhere between mid fork and the just above the top of the wheel. I also stated that specific lights may have locations where they work optimally based on their particular design.
Here's what the US importer of the Edeluxe, (and the light in question that the OP wants to mount) has to say about it:
The beams are brightest at the top, and become progressively dimmer towards the bottom. The road closer to the rider needs less light to appear as bright as the road further away. These progressive beams are like an automobile's low beam. In order to work as well as possible, the beam is designed with the height of the headlight off the ground as one of the parameters. If the beam is too low, the ground near the rider gets more light than is optimal. If the headlight is too high, the ground near the rider gets too little light.
So these German lights are all designed to work best when mounted at the fork crown, just above the front tire of a normal bicycle with 26" or 700c wheels. You can position them higher or lower, but the further you get from the top of the tire, the more the beam is compromised. Mounting at the handlebar still works well, but if you mount the light too low, the beam deteriorates badly. So I recommend against mounting lights at the level of the front hub, even though many people find that to be a very convenient location for a headlight. It may be convenient, but the beam will be poor.
YMMV, esp if you are using lights designed for hiking, caving, climbing, or technical single track.
Your downhill @ night with a dark sky sounds fun.
But I'm not really interested in getting into a 'mine's bigger than yours' argument. I feel comfortable heading downhill with my light mounted where it is. Lots of night riding and a rainy fleche has proven my setup to work, for me, on my bike, with the gear that I chose to use.