Originally Posted by
noglider
Good points, @
JohnJ80. I will be buying high-intensity lights from now on, and I'll be recommending them. It amazes me when I see people riding with lights that they clearly think are consequential but are not.
I do have some B&M lights that have received compliments on their intensity and focus even though they are low power, but I can't afford them for all of my bikes. My unshaped Cygolite headlight gets some respect.
I went on a rural ride today and had totally forgotten both of my lights. It was a sunny day, so I decided to continue. I was fine, but it's still better to ride with lights.
The other trick to pull off is to make sure to have enough charge in my batteries. That's why I prefer dynamo-powered lighting. I never need to tend to it. I use a rechargeable taillight on my bikes with dynamos, because I only need to charge the taillight once a month. A good headlight needs frequent charging, and I don't trust myself with that.
I got sort of interested in LED technology (I'm an electrical engineer in the semiconductor industry) and started tracking it in bike lighting back to about 2000. So I started collecting LED tail lights and comparing them to find what I could achieve with a given brightness. So I've spent a lot of time sort of comparing lights one to the other on both my rides and side by side at distance.
In a gross sense, I found that right around 60-100 lumens in a tail light, motorist behavior started to change significantly. I sort of attribute it to the red flashing tail light being bright enough to trigger driver attention since it starts to approximate car tail lights or emergency vehicle brightness at the very lowest end. That leads to reflexive responses and translated into drivers slowing down and going way wide around me at night. During the day, the effect is less pronounced but still there nonetheless.
I think the reason why it works is because motorists have sort of tunnel vision down the lane they're driving in according to the people who study this (found a lot of this on Cycling Savvy's website). So the more distinct of an attention interrupter the light is the more it encourages drivers to examine the shoulder and edge of their lane where we ride and see us from considerably greater distances. Once they see the cyclist, they take action. The farther back that is, the less surprised they are and the less anxiety it produces giving them the time and calmness to do the right thing by slowing down and swinging wide.
There are just a few lights that have low lumens and great optics that punch above their weight. They typically have narrow viewing angles where the light energy is concentrated down that axis. You can really see this when you compare the Bontrager Flares against other 60 or 90 lumen lights. It's right up there with the brightest out there that have significantly larger lumen output. But if you get off axis, then the intensity drops quickly which I think is an acceptable trade off. On axis, the Bontrager Flare seems to me to be as bright as my 800 lumen
Niteflux older RZ8 light which has an almost 360 degree pattern (i.e. no axis at all). I don't have the instrumation to prove if, but I'd bet that Bontrager's great optic means the intensity on axis is about the same as at a given point for the Niteflux. It just lacks the side visibility of the RZ8.
So I'm a fan of the Bontrager Flares (both the 65 lumen and the 90 lumen version. Both are excellent). They last a long time on a charge. They are small. And they are bright on axis. Good tradeoff. The Cygolite Hotshot starting with the Micro are all pretty good too (have great optics as well). Most of the other blinkie style lights are close to worthless.
Keeping track of battery charge is kind of a sign of the times. I'm not a fan of dynamos - I don't like wiring and when all is said and done, I like a little more power.