Are led lights bright enough?
 

Is a 100 lumen led light bright enough to ride in the dark? Have they improved in brightness since years ago?

There are led lights that put out at least 350 to 400 lumens. Look at the Magic shine thread. I have two flashlights that are putting 400 to 500 out the front.

Most of them are $400

... you really ought to listen to post #2.

Oh I looked at flashlights and they are alot cheaper for 500 lumens of light.

$90 for a Magicshine or about the same in Lights/mounts from Deal Extreme will net you alot of lite...Davidad pointed you in the right direction....

I have a Magicshine, and for $85 it puts out as much light as I possibly want for riding at speed even on bad roads. They claim 900 lumens, a couple of people have measured them at closer to 400, but even at 400 lumens, it's a heck of a deal at $85.

100 lumens will get you around, but you will have to take it easy; no riding at 25 MPH. 200 lumens is about the minimum that I personally would consider riding at full speed, and I'm not super comfortabel there.

I will probably get one of those.

I feel like a broken record - I should just put the dang thing in my sig.

Try the Terralux Lightstar 2 x AA if you want 180lumens in a no-wire setup. Runs for 1-1.5 hrs. Every bit as good as a Fenix. Mount on helmet with a rubber band or use a $5 Twofish lockblock on the bars. Drops into your pocket when you're done. $28 per light. Get two and you're good to go for front lighting in the vast majority of situations. (Probably not fast trail riding, but the helmet light option is really good, even if you have a Magicshine.)

But the magicshine seems to be the it-light for BRIGHT applications.

LED lights are so bright now they need to develop technology to keep from blinding oncoming drivers. I only put my dual P7 flashlights on high beam when I am on a rural street because of this.

100 lumens is a little too dim for my eyes at 20+ MPH, so I rock more like 800 lumens at full blast and maybe 400 on the busy streets. This costs me approx. $100 to do.

Yeah, they need the e-code reflector pattern with sharp cut-off like on European cars.

100 lumens is enough light to ride with IF you ride in relatively well-lit areas AND you don't ride too fast.

as for me, i used to ride with cree flashlights that are in the 50-200 lumens range, and for the type of riding i do, i get by just fine. however, i've recently picked up a magicshine light and have not looked back.

how efficient are those reflectors compared to the typical parabola-shaped ones?

for a headlight you want at least 2 watts. there are some decent single led units out there, but you might want two, with one set to strobe.

I just bought what I feel is the right light for my 26 mile round trip commute - it is 900 lumen and cost almost $100!

Why? If bicycle lights were positioned like a car's, there might be a valid point for the e-code cut-off (not that SAE would agree). However there are several reasons why that kind of optics isn't necessary. At least not from the standpoint of impact on other road users.

Start with road position. Mechbgon demonstrates pretty clearly in this picture

from this thread that we cyclists are too far away from drivers and have too little light output to seriously impact on on-coming driver. Even the e-code cut-off on lights is asymmetrical with light being cut off on the driver's side lamp but the passenger's side lamp reaches further down the road. Since we ride to the right of that passenger's lamp, we have little opportunity to cause glare problems. Our lamps are simply not that bright nor that concentrated. Most of the light is going to be along the center axis of the lamp with rather diffuse light to the sides.

Secondly, because of the lower lamp power and the slower vehicle speeds, our lamps aren't usually aimed that high. If the lamps are aimed high, the light is being wasted and not fulfilling it's primary function...illumination.

There is also the matter of cost. Optics are going to raise the cost of the lamps. With some lamps already costing $600+ for an okay light, adding optics will only add to the cost.

And let's not forget that lights were, and are, driven by the mountain bike industry. They were the first ones to notice a niche and they filled it. A light for mountain biking will work for the road but a light with a sharp horizontal cut-off won't work as well for mountain biking. Mountain bikers want the upward spill of the light to avoid overhanging obstacles on trails and a brighter, wider illumination.

And, finally, look at who is driving the portable lighting industry now. It's not bicycles. It's flashlights. We bicyclists are adapting the technology for our use but even mountain biking is a very small part of the portable lighting industry. Road...aka commuting...bicycling is and even smaller niche. There are only about 750,000 regular bicycle commuters in the US. Fewer still of those are darkness riders. That's not much of a market.

That picture shows saturation of the detector in the areas where the headlights are, so is not accurate regarding relative brightness. It DOES clearly demonstrate that road position of a bicycle has NOTHING to do with it also. That bike's headlight is easily equal in visibility as each of the car headlights in that pic. The car headlights are just larger diameter, and their relative positions on the front of the car makes the car more noticeable. Put two 6"diameter lights seperated by a couple of feet on your bike and you'll look just like a car, regardless of being three feet farther to the right in the lane.

LED bike headlights can certainly be too bright, if used in a belligerant, selfish and inconsiderate "retinal burning" way.

That's why an additional "strobe" is still a good idea even with a bright bike light.

I disagree about the use of a strobe on a headlight. On a taillight it's great. On a headlight it's just annoying. Especially when over a few lumens. Headlights for bicycles are the only ones that strobe, and that's only because LED are easy to strobe and marketing hacks do it to add another "feature" to their product boxes.

Motorcycles and scooters riders have been being hit and killed for many years and none have ever strobed their headlights to reduce the risk. Why no strobe lights made for bikes before LED made it extremely easy, if there's such an important benefit? Because strobes are NOT a good idea for a headlight, from the viewer's perspective. And an SOS signal is NOT a strobe.

Both lights...the bike and the car...have equally saturated the camera's ccd. Since the picture of the bike's lights and the picture of the car's lights were taken at the same time, it cleanly shows relative brightness. And the relative brightness was the point of my post. The relative position of the bicycle vs the position of the car to on-coming traffic was the point of my post..which you clearly missed.

mechBgon's picture is on an obvious 4 lane highway. His position is, at a minimum, 22 feet from the on-coming traffic lane running parallel to his direction of travel. It is probably closer to 30 feet. Even if he were running a lamp that were the equivalent of a car's (he's not) and a huge beam spread, there is no physical way his light could cause glare for the drivers in the closest on-coming lane. He is too far away for it to be an issue...as are any bicyclists in most any night riding situation. Perhaps on a left turn but even then, the bicycle is positioned more like a motorcycle than a car. Or perhaps you have a problem with motorcyle lights too.

Then why do you use a Magicshine 900? The advertised light output of the lamp is 900 lumens. That output is very near that for a automobile lamp. Isn't that belligerant, selfish and inconsiderate? Before you tested the lamp, you could not have known that the lamp wasn't putting out 900 lumens. Or do you subscribe to the 'do what I say, not what I do' school of hypocrisy?

I bought maximum lumens/dollar. I bought the ability to use more light when NECESSARY, like with wet streets, but not always. And I don't use three of them, with one on a helmet ignorantly pointing in car drivers' faces.

By the way, that road in the pic is a curve with the photographer on the outside of it. The bike light is on the handlebars, pointing more into the curve than the body mounted lights on the cars.

Bike lights can easily be too bright, in my opinion. They're so bright, we're having this agrument. But I work with LEDs, and am the laser safety engineer for the companies I've worked at for the past 25 years, so what do I know about it?

I don't think I'd really want to go with less light than my MagicShine (probably 400-ish lumens, as noted by other il-lumen-aries above :)).

100 lumens might actually be enough for riding in complete darkness, as long as you're not doing any mountain descents or MTB tricks. Where I find I need more light than that is in heavy automotive traffic or in areas with irregular illumination of the ground. That means there's more than enough light to kill my night vision, but I still can't necessarily see that upcoming pothole or ice patch without a good light source of my own.

Looking at the comparable numbers for cars--quick check of Wikipedia--Halogen automotive headlamps put out about 1500-2000 lumens, and HID systems are around 3000. All of these numbers are per bulb, so most bike headlights aren't anywhere near car-headlamp territory (though some of the brighter ones can be a bit of an annoyance to oncoming MUP users if they are aimed too high).

+3 on this line above... Link for MS Light for OP..

http://www.geomangear.com/index.php?...k3tl7a0hejgt31

my 1st night commute was in the rain with a 1 watt strobe up front. it was psychedelic to say the least. plus I couldn't see a dam thing in the road.

Thread is reopened. Let's keep it civil now.

I took a shot at a cutoff modification to see how effective it was. The light I used was a Lumapower MRV SK with the OP reflector. I used aluminum foil between the reflector and lens, like this:

http://i240.photobucket.com/albums/f...n/IMG_0083.jpg

The beam looked like this:

http://i240.photobucket.com/albums/f...on/cutoff2.jpg

I stopped the bike on a dark 2-lane highway and walked out ahead of the bike so I could see how effective the cutoff was. It was not impressive. I went back to the bike, flipped the light over so the cutoff was now an anti-cutoff, and walked out to observe it again. There was no perceptible difference to me as a pedestrian. So much for that plan. I see people advocating cutoff-equipped lights quite often, but I don't think many have done any first-hand research.

For me, I would need to ride pretty slowly, with no competing light sources, to manage on 100 lumens (by which I mean, see and avoid road hazards, not just stay on the road). The darker it is, the less light I need, since my night vision can adapt to its fullest in darkness, but 100 lumens is a little skimpy.

The photos above, that show my bike next to a car on a highway, are from this video, for those who might be interested in the source: http://www.youtube.com/watch?v=ThwjZ6j11mc It's an out-&-back, so skip to about 1:40 if you just want to see headlights. The bike has a DiNotte 600L and a Dereelight DBS V2 with the OP reflector (DiNotte: 600 lumens and floody, DBS V2: 250 lumens and focused). I also have a 140-lumen Fenix L2D on the helmet. At the point shown in the photo, the DiNotte is responsible for most of the light reaching the camera... it's actually not much good as a highway-riding headlight, but the "shotgun" beam makes it good for safety purposes in the city because it appears intense from a wide angle of approach.