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These are annoying for several reasons:
These lamps should be banned if they can't make the colour more like neutral or warm white. Also, the regulations for car headlamps are not good enough regarding side spill where the light is essentially not cutoff, see this section.
Various LED lamps in particular have artefacts. I would describe this as seeing very bright rays (from a background of far less bright light) emanating from a lamp, even though it's supposed to have a homogeneous light beam. With the camera I could see the exact same thing I experience with the naked eye. Here are some examples of the Edelux bicycle headlamp (which uses a smooth reflector) and a LED street lamp which is unbelievably annoying:
|In both cases, look closely at the full size pictures and look at the edges of the light, where you will not see evenly distributed light, but a sun like effect: Around the main light you see 'solar flares'... These are what irritate me. It's not surprising as this means the eye gets to experience very large differences in intensity with a very small change in direction, which means when you are moving this happens: in certain spots in the eye the amount of light received is low, and when slightly moving it suddenly becomes very high. You will experience this as sparkling.|
Schmidt Edelux headlamp at 20 m distance:
The Edelux isn't that bad, but it could be better. You will definitely experience some sparkling when encountering this lamp.
Here's a LED street lamp, located in Leimuiden (on the Raadhuislaan). Pictures are from 50m (it's the one after the first yellowish one, and there are 3 of those LED street lamps in a row), from 20m, and straight up (in the camera picture the annoying artefacts don't show at 50m/20m but in real life they are very much obvious at even larger distances):
This is one of the worst lamps I've ever come across... I've made closeups of older street lamps and they are perfect, light distributed evenly, no sparkling and nothing shows up either on the camera pictures. See these for example:
In torches, a so called 'orange peel' reflector is often used, which will give a more homogeneous beam. This is in fact the same type of problem but with torches you don't really look into them, so it's about preventing irregular (though mostly circular symmetric) lighting patterns, i.e. brighter or darker rings. It will also give a smoother transition from hotspot to the outer area. But it will be difficult to make such a surface work with a reflector that has to have strict cutoffs. Perhaps the rule makers should look into the problem of artefacts; a smoother cutoff could be desirable when lamps become stronger as artefacts give a blinding effect just like too much light does...
Suppose we have a beam with cutoff (e.g. as in the Schmidt Edelux). To give a homogenous illumination of the road surface (as experienced by the cyclist, I don't mean the light density of light from the headlamp onto the road surface far away should be the same as close by), more light needs to go to the farthest section, because:
This means, that if you were to make a lamp that has a truly homogeneous illumination of the road surface as experienced by the cyclist, a lot more light will then have to go to the road surface far away, and the light density (light per area, i.e. lux) at the top of the beam is far more intense than at the bottom of the beam (= the part that illuminates the road close to you). [ example picture/calculation/estimate to follow ].
Now consider a cyclist who has incorrectly set his headlamp such that the cutoff is above the horizon. This results in oncoming traffic getting a very intense beam of light shining into their eyes. This means that a mechanism to be able to properly and finely tune the lamp's angle and a bracket that doesn't bend if you put a fair amount of force on it, should be included in powerful headlamps (this is notably absent in all bike lamps, and with lamps such as the IQ Fly, IQ Cyo and Edelux, it is necessary). Far less strong bicycle headlamps with cutoff, halogen even, that are incorrectly set up by a cyclist (pointing up) are already extremely irritating.
That this really is a problem is obvious from what I have experienced: I have on a few times ridden with an Edelux headlamp set such that the cutoff was above the horizon (due to unwanted changes in angle because the lamp bracket got bent due to a handlebar bag touching the Edelux). In those cases, I always got flashing headlamps from cars. Now consider the following: Several times I rode with the Magicshine at full power (on purpose) on the same road (a 10 km ride), and got no flashing car headlamps. The magicshine was undoubtedly annoying, but the incorrectly aimed Edelux much more so...
Some rear lamps are very bad, as their light is not diffuse. With a headlamp you're going past it quickly enough, but with a tail lamp you can be stuck behind someone (where there's no room to overtake) for a while at a very short distance... So a rear lamp should have a diffuser. I've not tried the new B&M lamp with the bars (toplight line plus), this could be better from what I heard. I've got a Toplight flat plus that is not diffuse enough, but there are far worse ones. On forums of candlepower and mtbr.com there are people talking of a 3W rear lamp and that's just insane. Unless done properly! E.g. car rear lamps are much more powerful than those of bicycles, but not annoying because they are
There is an exception (of course): Some new car rear lamps use LEDs that are pulsed at a low frequency, which makes them annoying. When the car turns left/right some distance in front of you, you see this particularly well. This attracts attention and is therefore bad. (It's just unbelievable how inane some of the designers of lamps are, come on guys, do some tests yourself!!! (I should add a few hundred exclamation marks here)).
Examples/pictures of bad rear bike lamps to be added...
Flashing rear bike lamps are only good for one thing: To save battery life. It makes estimating distance extremely hard and it attracts too much attention. They are also illegal in several countries such as the Netherlands and Germany.
On a rainy night I encountered someone with a strong flashing front lamp ca. autumn 2008, and I blurted out 'gek' (idiot, or better translated probably 'nutter') to him as this is perfect to blind oncoming traffic. It's hard enough to see anything in the rain, without some idiot coming with a (strong) flashing headlamp that kills your night vision. Manufacturers who make flashing front lamps need to get a reality check and people who use them need to get some education as to why this is bad. And again, flashing front lamps are illegal in e.g. the Netherlands and Germany.
I'm not fond of daytime lamps on cars nor bicycles, at least when they are the main lamps that are lit, not sure about additional lamps that some cars have as daytime lamps, or that the new (August 2010) B&M Cyo T / Cyo RT for bicycles have. There are several reasons why:
this section will be expanded.
A new generation of traffic lamps is being used, LED based. The designers seem to be morons as these lamps are way too bright at night. Depending on the precise direction they are pointed at, they shine into your face as if someone were shining with a torch in your face. Also, the green LEDs are the worst which seems to indicate that these traffic lamp designers don't even know the human eye is more sensitve to green than to red. I've made pictures which clearly show the problem (of too much light in particular):
The first picture is a bit blurry, and picture with the traffic lamp on green is exposed 3s instead of 4s. Both pictures are from almost 100m distance to the lamps. The road surface is a bit wet from rain some time earlier which is actually why you can see the beam pattern and amount of light so well. It's not that obvious normally on the road, but from this you can get an impression how much these traffic lamps shine into your face. Ridiculous!
Here are some pictures of a parallel road and the problem of too much side spill at eye height from lots of car headlamps. Between the road on the left (for cyclists and local traffic such as tractors) and the one on the right lies a patch of grass about 4 metre wide.
The following pictures were taking 23 June 2010, at about 22:16 in the evening and even with plenty of light, many of the car headlamps are very annoying:
These 3 were taken a few seconds apart:
About 30 seconds later, these 3 were taken a few seconds apart (first car as seen in pictures 1 and 2 has excellent headlamps, no irritation at all, the second car as seen in pictures 2 and 3 has bad headlamps):
Now at night (from an earlier night), completely dark.
Here's a car with ok headlamps:
Cropped to show just the headlamps:
A bit later, a car with very annoying headlamps (and from the light colour, you can see they are just a halogen headlamps, not HID!), just look at the huge cone of light coming toward me:
Cropped to show just the headlamps:
The result of such bad lamps, is that before I had an Edelux headlamp on my bike, I often could not see the road when encountering cars with such bad lamps, and this was especially bad on rainy nights. For riding on roads parallel to a road only for cars I consider the Edelux to be the absolute minimum needed to be able to cycle safely.
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Last modified: Fri Dec 21 10:46:59 CET 2012