How can I know the actual brightness of xxx lumens (or vice versa)? All I know is that all the flashlights I've bought have much less lumens than claimed (an "1800 lumens" flashlight is dim enough for anyone not to believe its claim). It is hard to tell how bright a light is from videos.

Lumens are sort of meaningless.....Lux is what the lumens actually light up.....You can have 2000 lumens and 20 lux....or you can have 200 lumens and 40 lux.....depends on the reflectors.

Raw power only gets you so far.....depends on what your trying to light up....the road and/or everything else.

Or who the individual is trying to impress in a Mine is Bigger/Brighter than Yours contest. The standard of measurement for this "mission" is either lumens or how many others indicate they have been blinded or annoyed by the Light Power Ranger.

I came across this review https://www.visualexpert.com/Resources/motheffect.html which concludes "The "moth-effect" is a myth in one sense and reality in another. The idea that drivers may steer off the road when they fixate flashing lights is likely correct, but they are not drawn to the lights like moths to a flame. Rather, they inadvertently steer rightward, which may or may not take them into collision with the roadside vehicle." They also note that 'Neither study, however, employed bright lights, so it is unlikely that the "moth-effect" results from an innate phototaxis.'

So it sounds like you're both right.

I can tell you anecdotaly that I can be completely blinded by an approaching bike light that comes within a few feet, with impaired vision for two or three seconds. It's not a literal physiological blindness, as you point out, but a temporary loss of the ability to see anything in the direction of travel.

I think it's true that we have a tendency to steer towards where we look. However, clearly we can train ourselves not to do so. Otherwise, we wouldn't be able to keep our vehicles (cars or bikes) tracking straight.

its just a matter of time before cycling lights are regulated. 2000 lumens is serious firepower even if you are bombing down a trail at 25. its hard to imagine where this could possibly be needed on typical urban streets.

Yes, I do not buy into the moth-effect, nor was I referencing that. People do tend to look at something they are distracted by though and often this is a light that is shining in their eyes irritating them. Since I do a good majority of my driving and motorcycle riding at night, I tend to notice this a lot, and have to work at not staring at a light that is blinding. Of course that is all part of being an active, attentive driver, unfortunately many people, most, are not. I prefer not to shine lights into their eyes. Keeping the light properly adjusted prevents that for the most part.

There are reasons for lighting regulations. It is good to be see, and to be able to see. A bright light is essential for me while riding in town around traffic, but I don't want it shining in their eyes. For one thing it is rude, for another it makes it difficult for them to see anything else, for yet another I don't want them to have yet another reason to decry bicyclists. Thankfully I have the respect of the police in my area when they see my bike properly lit, as well as a good number of car drivers who have talked to me and commented on my lights.

What about our rights? Some of us Light Power Rangers need to arm ourselves with as much lighting firepower as possible in order to accomplish our mission. At least that is what I gather from some of the BF posts on this subject.

They are wicked bright too.. They are regular flashlights that can be purchased on Ebay,DX, and Manafont. The ones in the first picture are 18650 big heads and they cost about $27 each, the second picture are 26650 lights, the small one cost $22 and the bigger one, I caught on sale for $38, all prices are with free shipping. Mounts cost about $2 each..

Burn time on all of them are over an hour, except that triple. That triple might be just at 1 hour. My commutes are about 20 to 30 minutes. I carry spare batteries, plus I have charges at home and work. Also, since I am running double up front, plus a big on my helmet too, run times don't even come into play.

Might as well show the helmet monster.. a 26650, rated lum rated, at 1600 to 1800. But, in all honesty, I would say it puts out a mean 1200 lums..






I am not taking chances with my life. BTW, with all brightness, (which are aimed at the ground in front), I haven't had anybody steer toward me because of the brightness. What I have seen, is that everybody and everybody's brother and sister give me my rightofway,and much respect.

:

Was getting a propane tank filled at a shop across the street from a big Harley dealer. Propane guy is really chatty, the conversation turned to motorcycle & bicycle lighting. Turned out he's an ex-cop & he noted the light fixation problem which I hadn't heard of, although he was referring more to having lots of lights (oldsters might remember when Electra-Glide owners used to festoon their motos with numerous lights). Well lately on the bike path I've seen more cyclists switch lights to lower brightness when approaching other bikes/peds. Actually it seems like back when some bicyclists had powerful HID's that freight-train glare was more of a problem. BTW the new trend is guys keeping headlights or more esp rear blinkies on during daylight. Yeah, rechargeable batteries make it cheap to do but seems a little silly on a bike path.

I encountered a driver on a dark road tonight. He yelled at me about my lights. "Good lights! Good lights!".

When I am driving at night, my main dislike about cyclists are the ones who are so dark that I can't see them. Well illuminated riders makes my life as a driver better, because they don't stress me out. I have never seen a cyclist with a light that threatened to "blind" me, even slightly. But I frequently encounter headlights from oncoming cars that are so bright that I have to look away.

How can that be, since some of us have such fearsome lumen-power? I think it is a question of range and movement. Sure, that 1000 lumen light fixed in our eyes, head-on at five feet range, is blinding. When does a driver ever stare at a cyclist's light head-on at five feet range? That same light across an intersection - fifty feet or more - bobbing and waving, is nothing special.

You got that right.

Better too bright than cyclist dead. Pump out as many lumens as your dreams and budget allow is the way I encourage.

+1

I suggest you go out on your typical urban street some night and count the lights that you see in a 300' to 500' distance. Make sure to include an intersection. Even better include an intersection on a major arterial street. I would estimate the number of light sources in that distance to be well within the range of 1000 and probably more. That's a lot of competition. A light that is 1/10 of what you use out on the trail is going to be lost in the background.

Can't be said any plainer or better!!

MTBR's light shootout now has an integrating sphere to measure the total light output. Of course, that doesn't say how wide the beam is, or how evenly it lights up the road.

Their review navigation between pages is confusing. Try googling "MTBR shootout + your light" to find it's page.

For example:
Magicshine 808 Claimed 1000, actual 648 lumens

Lezyne Mega Drive: clained 1000, actual 1140 lumens.

There's more lights on the 2012 shootout pages
The Backyard Beam shots are good for comparing the light's coverage.


I don't know of any tests for the under $50 lights. Their actual lumens might be 1/2 or 1/3 of their claim. But that's still a lot. Their beam patterns are probably fairly uneven, with a bright hot spot in the center. Not bad for the price, but I'd bring a spare light in case the primary light fails on a ride.

Are those the only two choices?

Common Sense!! ​

If a bright light is coming toward you, WHY look at it??? IMO, that is "common sense" not to look at a blinding light!

If everybody steered toward bright lights, with a zillion cars running with the brights on all the time, it would be mayhem out there.

Cars run their brights a lot. I can say that 1 out of every 20 to 25 cars got their brights on. Also, 25 cars can pass in a matter of seconds, or less. So, bright lights coming from cars is a reality. Now, people want to regulate bicycle lights?? I know I am missing some of the cards out the deck, but I be dam if I am missing that many!

Also, show me the results of bicycle with bright lights killing people in cars? I can show a lot of cars killing people on bicycles, where is the beef to the argument against bright lights on bicycles???. Bright lights coming at me, I am looking where I am going, not at the lights. First off, looking at bright lights, is going to make me see spots, and I cannot see what it is back of the lights, so why look at them. They are not coming at me?? These are straight common sense questions.

So, all you peeps that are getting your arms twisted to look at the bright lights, try it another way, don't look!!!

This pretty much spells this out, and since most bike lights and flashlights tend to have small hotspots for distance and very limited spread, they're great for attracting attention, less effective at lighting the complete lane up efficiently, and not too likely to nail motorists unless deliberately pointed at them. I'd say the biggest place they might be a danger for oncoming traffic is on a narrow bicycle path where they're least likely to be used at full power.

There's a reasonable limit to everything, but again, its normally determined by lux and not just lumens. 200 isn't worth worrying about and 2,000 would only be an issue for motorists if it was coming from a major flood-light source - which would definately encroach on their lane even up close.

LOL - even when I took drivers ed some 30 years ago, it was emphesized to NOT LOOK AT ONCOMING HEADLIGHTS. So even people with no common sense should be clued it to that if they have a driving permit!

I too have received way more compliments than complaints on my lights over the years, both from pedestrians, bicyclists and drivers.

But I've never seen any cars have trouble driving around me due to the lights, unless you count the ones who changed direction to keep from running into me after they noticed me due to my lights. Another things I haven't noticed is automobile traffic having any problems when they approach form a 90 degree angle. My route takes me across a pair of 4 lane roads, and I often have to wait for traffic. I've never seen a problem with traffic not being able to continue in a straight line after passing me. Don't these drivers know they should be having the troubles some of you have mentioned?

Sometime ago there was a picture posted here of a bicycle under a large dumptruck after a fatal accident. The driver never saw the bicyclist until after the accident, and in one of the pictures you could faintly see the dim glow of a nice polite low powered light that wouldn't offend anyone still shining after the accident. I don't want to end up like that.

Yep, I agree, unfortunately common sense isn't as common as we once thought it was.

So the solution is just "don't look?" Why do we dim our brights when driving then?