BarracksSi

More dyno-powered lights, with and without cutoff beam patterns, posted at Peter White's site -- look at the bottom image and see how much more light is on the trees than is shining at the same height in the automotive HID pics I posted earlier.

B&M Cyo R -- beam cutoff:


Supernova E3 Asymmetrical -- beam cutoff:


Supernova E3 Symmetrical -- NO beam cutoff:

Juha

Like I said, I prefer the Supernova with cut-off beam for commuting purposes. That said, for any valid comparison between various lights, the photos should be taken from the same spot, with the same camera and settings and at approximately same time. Too many variables otherwise. That's what Peter White does (the B&M Cyo and Supernova photos above are from his web site).

Arcanum

Those are some really freaking bright lights. Based on those pictures I could definitely see them being a glare/blinding hazard at night if they are aimed high enough.

ItsJustMe

The only time I need lights is in the winter, and in the winter I'm slow and tired enough already without making me power the generator too.

Also generator lighting is a lot more expensive. I can buy a P7 flashlight that's more than bright enough for my commute on medium, which gives me 2 hours runtime per battery change, for about $60 with batteries and charger. And I could move the flashlight around to any number of bikes trivially.

chico1st

yeah i bike in the city... i can only see needing lights like this in severe snow/rain storms

cyccommute 

Exactly. Let's not compare chalk to cheese.

There are variables here that need to be considered for a valid comparison. Where is the beam aimed? For cars, the driver's side is aimed at between 20 and 30 meters (65 to 98 feet). The passenger's side is aimed at about 60 meters (196 feet). A bicycle lights are usually aimed much closer...probably more like 16 to 30 feet. You should also compare the light thrown off by the passenger's side lamp because that's where we ride. A bike light aimed that far down the road would be useless for illuminating the road and would cause glare.

You also should compare lights in similar situations. In each of the car photos the lights have nothing overhead so we can't see what kind of light is cast upwards. Hint: It's not zero. Take pictures of your backyard with car lights from the same place and same light conditions as well as same camera settings and get back to us on how much upward spill there is.

Even the pictures you show from Peter White aren't that great. The camera has been moved between shots. The Supernova E3 symmetrical photo looks like the camera has been tilted upwards and all three shots don't show the same position. One is wider (see the white cylinder on the right of the photo) and one seems tilted up more.

The SAE standard allows for more upward spill to illuminate overhead road signs not signs on posts.

Finally, glare can't be measured from behind the light. That only measures illumination. You have to have the light shining on you to judge glare. For the most valid comparison of glare a camera would have to be set at eyelevel for

1. a motorist in the most common car in the US (a Toyota Corrolla)
2. a cyclist
3. a pedestrian

The light sources would have to be the Corrolla lights and a bicycle light of average output...around 250 lumens. Multiples of up to 3 of the 250 lumen light could be used. Higher output bicycle lights could also be used.

Pictures would be taken with the aperture setting and shutter speed locked so that it wouldn't over expose for the car lights. Light position and distance from the camera would have to be fair. Set the distance from the lens of the camera to the light at 25 m. However the light would be set 3.9m (13') off the axis of the camera to take into account the most common position of a bicyclist on the road.

For assessing glare from car to car...a control if you like...the light would be move in towards the camera's axis so that the separation distance is closer to that of a car to another car...say 0.75 m.

For the pedestrian, the bicycle light would be compared to the passenger's side light of the car with no offset for the bicycle light and 1m for the car light.

This would be a fair assessment of the relative glare of bicycle lights vs that of cars. From my observations, cars have far more glare than a bicycle can ever put out because their light output is far higher than most bicycle lights.

CliftonGK1

Regardless of lamp design and power source, I've never had a driver complain (flash their brights) at me over one of my bike lights. I have an L&M Solo 13W halogen, a B&M IQ Cyo, Schmidt Edelux, and Supernova E3 (first gen.) The first and last lamps are non-cutoff, the Cyo and Edelux are cutoff lights. Either way, I've never gotten driver complaints.
The only complaints I've recieved have been from one dude on the MUP (much different viewing angle than an oncoming driver), and he's complained equally about the E3 and the Edelux.

Rob_E

I just switched to dynamo lights last fall, and I love them. Got a Shimano hub in a pre-built wheel that looked to be about the same price, maybe even cheaper, than buying parts and building it myself. The lights were relatively cheap Spanninga lights I bought from Velo Orange. LED, standlight, auto on/off. You can get cheaper lights if your goal is primarily to be in compliance with the law and hopefully to be seen on the road, but if you want the light to help you see your way, you need to spend the extra money or make your own lights, although that can be trickier, and I don't really know how much it will save you.

I have a 2nd, battery light that I use when I'm away from the city lights. I can get by with just the dynamo, but I feel a lot better with the brighter battery lights. But soon I hope to replace my Spanninga with something brighter and remove the battery lights entirely. There are also some really cheap halogen lights, too. Some of the downsides of halogen lights have already been discussed, but something else to consider is bulb life. I blew out a halogen light in a few weeks by running it without a tail light. This can be fixed by either adding a tail light or by replacing the 2.5 (?) watt bulb with a full 3 watt bulb. But even with this change, halogen has a much shorter life than LEDs and can still leave you in a lurch with no light when they burn out. Still, if you want to switch to dynamo and get on the road cheaply, they may be worth looking into.

Theft can be an issue, but it hasn't been for me. Although I tend to leave my battery lights on the bike, too, and they haven't been messed with, either. But most dynamo lights bolt on, so someone really has to want them. I also run my U-lock through my front wheel and frame to keep it safe. The rear wheel is bolted, and I have a ring-lock to make it more of a hassle to steal, so I don't worry about that, but that's not as good of an option for someone with quick release wheels. I hope to get some PitLock skewers or something similar for my front wheel so I can make theft even less of an issue. But if you're worried about theft, it's good to consider that the dynamo system is generally more integrated and attached to your bike. This is good because they can't be stolen easily, but bad because they can't be pocketed easily by you if you know your bike will be sitting out for a while. Hasn't been a problem fo rme, but it probably depends on where you're located and where you're parking.

exarkuhn15

I bought several of those micro FF LED lights from them, too. I don't think any of them lasted more than a couple of rides before the electronics failed. I took them apart to try to resolder and it was easy to see why - super cheap. The rear ones were fine, but those front ones were pretty worthless. I upgraded to real B&M front lights with a mirror, and I couldn't believe the difference. Like the difference between a cheap flashlight and a car's headlights - no joke.

Rob_E

My Spaninga lights have been a mixed bag. The front light has been reliable, if not terribly bright. I continued to use it in tandem with a battery light if I was going to be away from the city lights. The rear light is unreliable. I don't know if it's a bad connection or some other problem. It's difficult to diagnose because it has no switch, but just a light sensor, so it's hard to know if it's not coming on because it's not working or because it's not dark enough. I should have just got an "always on" light and let the front headlight control it. Plus it doesn't come on until the front light has been on for a minute or so.I just replaced the front light with something more powerful, but I haven't had the chance to put it through it's paces yet, but I do think it will outperform the Spanninga by a large margin. Still, the Spanninga will likely hang around on my back-up bike, since it's been very reliable.

fietsbob

3 bikes with Jump on them and ride LED lights 559 406 & 349 wheels ..

have a Battery light also for the ones that dont see regular service, I believe you can make your own choices ..

PaulRivers

Lol, this thread is from 2010. I saw it yesterday - the person who opened it had a new account and posted small text and a link, it looked like spam so it probably got deleted. OP might not still be following the thread. ;l-)

Nikolaus

The hub dyno is always on. So I always use lights. Day and night and summer and winter. When I enter a shade in summer, my lights are on for others to see me.
You can get rear lights that light up more when you brake. And some 150 lux front lights make the night a day. Newer lights come with capacitor to stay on when you stop.

I grew up with a bottle dynamo at the bike. To increase traction in ice and snow we added bottle caps to the dyno wheel rubbing against the tyre.

But once using the hub dyno I got hooked.

And in Germany bikes come with hub dynos off the shelf. Got me a 63cm trekking bike with hub dyno, full lights and reflectors and mudguards ready to commute for £360 including shipping to UK.

Just had to change the seat post into a longer one for my 36" legs. Yes the bike is heavy but so am I. It doesn't make much difference.
and as there is always glass on the road on Monday morning, had my tyres changed too.

rhm

Old thread!

Some of this was already discussed ten years ago, but in case anyone hasn't read the whole thread, the better LED dynamo headlights have a headlight beam shaped for maximum light on the road, not elsewhere.

i have ridden all night team events a half dozen times, and the difference between dynamo lights and battery lights is striking. The battery lights light up the trees and everything, a lot of light where you don't need it, and your eyes adjust to that. Dynamo lights do not produce that much light, but it falls where you want it, with the result i see better.

When another rider with battery lights is behind me, i cast a huge shadow up in the trees, something my dynamo light doesn't do.

Gresp15C

Granted it's an old thread, but... the method of powering a light, and the method of forming a beam, are separate design issues.

A lack of regulation, combined with a proliferation of confusing ratings (Watts, Lumens, Candela, Lux, etc.) will lead to an arms race for poorly engineered, or un-engineered lights. A powerful LED surrounded by a tiny parabolic reflector and fed with unlimited battery power will look sexy on the bike and produce the effect you're noticing, lighting the trees and blinding oncoming cyclists, especially when the lights are helmet mounted. It's a pet peeve of mine.

A minor exception to the above rule is that a dynamo produces a limited amount of power, so you have to be more sensible about how the light is designed.

A light that's well engineered can put the light where you want it, with a limited amount of "spray" for visibility of road signs, etc. The Busch and Mueller lights work that way.

Long ago I got some training in lighting design, though I've not done it commercially for a long time. Today, I design optics, but not for lighting.

Gresp15C

One more thing, also since it's an old thread, is to note that incandescent and halogen (a type of incandescent) are probably obsolete at this point. LED's are just so much more efficient, and last longer. Incandescent lights go on the same list as steel rims, in my book.

sweeks

Hub and "bottle" dynamos are actually *alternators*, producing AC, not DC. The term "dynamo" is technically reserved for generators with commutators that produce DC (I did not know this... Bottle Dynamo, Dynamo).
The only consideration in which lights to use is whether they will operate on AC. Most battery-powered lights are designed for DC and may not work well (or at all) on AC.