For fans of my "beam shots captured in a dark bathroom" series (which is gonna get a gallery show someday, I swear), one caveat -- my camera (a.k.a. my phone) has been through several purported "upgrades" since I last went on a headlight photography binge, so any comparisons between this post and previous lighting posts should be made at your own risk. Bad science? Probably. But still worth precisely what you paid for it.
Anyway, as you can see, ol' Knoggy puts out a fairly blue light, round beam, bit of a corona, and some odd shaded bits mid-beam. I've used this as my only commuting light a few times, and in a city setting with plenty of ambient light, it gets the job done. I wouldn't count on it as my only light source on a dark, unfamiliar trail, though.
What I really do like about the Knog (and its matching tail light) is the hipster-approved rubber strap mounting system that makes it easy to mount on handlebars, seatposts, fork blades, seatstays, helmets, and small pets. Thus, I've put both of them on my helmet, thusly:
Irony alert: I wasn't able to stretch them through the minimal vents on my hipster-approved skater-dude helmet (shown in my photo over there to the right), which is even more appropriate since hipsters love irony. So, as you can see, they're adorning my go-slightly-faster space alien helmet. The tail light is angled to mount on a seatpost, so I had to flip it over to keep it from pointing into space and annoying Martians.
Other nice things about these lights: Each one runs on two AAA batteries, which makes them a) easy to recharge, b) easy to replace, and b) not terribly heavy upon my melon. So, while they definitely fall into the "be seen" category rather than the "light up every pebble" category, I'm happy to have them up there as a supplement.
To what, you ask? Guess you'll have to read my next post.
Obligatory Disclaimer: I was given these lights -- not by Knog, but by my in-laws. And while they did allow me to marry their daughter, I've done my best to not let that color my judgement in this review. Oh, and if you follow that Amazon link and buy stuff, I eventually make a few pence on the deal.