Creatures of the night

As I previously noted, I'm gonna be competing in a 12 hr race the end of October. In a 12hr race you're gonna do some night riding(which I've only done once before), so I'm gonna need some lights for the event. One of my teammates, Dave, loaned me some nice HID lights to try out. Riding at night is weird. Trails you thought you knew, become new trails.

What is Dave measuring?

Now I've got to dig up my own set of lights, and practice with them...because if I ride as lousy at the 12hr race as I did tonight-ouch!