Dazzling or Bright - where is the dividing line?

[deliquium]

ahem, as mentioned on page 1& to save those talking about fitting alternate mirrors and blocking the beam in other Heath Robinson ways, from a bodge too far.

If you use a magic shine or equivalent this will be the best not quite £6 you can spend for it - they really do work for you seeing the road ahead and for the poor dazzled onlooker http://www.amazon.co.uk/SEEN-ANGLE-DIFF ... and+b+seen

+ 1 These diffusers really do transform the usefulness and sense for these particular (Magicshine and inumerable copies) lamps.

[blackbike]

...or that chavvy habit of driving around town with fog lights on just because it is dark.

Maybe the memories from my younger days are somewhat tainted (greener grass and so on) but it seems like more and more cars are now being made with at least 4 headlights (besides the DRL's) and a great many motons are choosing to illuminate all of them.
If memory serves, in ye olde days cars only had 4 headlights if the owner went out and bought 2 more to be fitted to the bumper.

Dunno when your younger days were but there have been cars with four headlamps for a long time now. From memory the Mark x Jag(1961), Zodiac mk 3(1962), Rover 2000(1963) and Triumph 2000(1963) all had four headlamps and, apart from the Jag, were all big sellers.

Yes, but people didn't drive around with all their lights on all the time.

I think many motorists now are really pleased with the gimmicky lights on their cars and are eager to show them off.

They do seem to be easily thrilled. Remember how many of them couldn't resist a silly racing car style aerofoil on the boot or bull bars when they were fashionable.

[bikes4two]

ahem, as mentioned on page 1& to save those talking about fitting alternate mirrors and blocking the beam in other Heath Robinson ways, from a bodge too far.

If you use a magic shine or equivalent this will be the best not quite £6 you can spend for it - they really do work for you seeing the road ahead and for the poor dazzled onlooker http://www.amazon.co.uk/SEEN-ANGLE-DIFF ... and+b+seen

Ahem, without meaning to be argumentative at all, I've looked at the link above and the associated pictures, especially the two showing the beam pattern before and after fitting the diffuser. It seems to me that with the diffuser fitted the main beam covers a much wider area with 'bright light', thus increasing the probability of 'dazzling' someone in front of the light if the light down angle is not correct - no?

[MikeF]

What I'd love to see is a light made by the joint efforts of B&M and Cree.
B&M would provide the reflector and dyno technology to give the Cree LED just enough juice to run at low beam. Cree would provide their battery in conjunction with the dyno to bring their afore mentioned LED to full power when main beam was needed.
In my little fantasy world, the dyno would also trickle charge the battery when not in use to provide power for the main beam and charging capabilities.
If only.

Cree don't make batteries. If you have a "dynamo" sounds as though what you really need is a high and low beam setting. You could bring into use an extra LED on the high beam if you want more light. No need to faff around with batteries.

[JohnW]

There are two problems here, aren't there?..........

Yes, indeed, two problems.

To be fair, I think it's quite rare that an oncoming cycle is bright enough to be dazzling to another person on a bike.........................Yes, the big problem is the behaviour of drivers. Maybe it's because I cycle too that I spot nearby bikes, but actually I'm pretty sure it's not that many drivers can't see riders - it's that some either don't remember how to interact safely or just don't care because what's the worst that can happen to them? A scratch on the car that their insurance will pay to fix and a slap on the wrist from some magistrate who thinks it's OK that a driver can't tell the difference between hitting a pothole and hitting a person!......................

It seems that a lot may depend upon the Greenway/cyclepath that we ride on. The Greenway that I use almost daily does have a lot of cyclists who ride with dazzling lights - in fact at the evening commute they're there in droves. On another Greenway that I use quite regularly I rarely see another cyclist after dark, but that one isn't on a commute route.

With respect to your points about drivers and on-road riding, it seems that our experiences are very similar and we've arrived at similar conclusions which have generated similar perceptions.

[pete75]

Maybe the memories from my younger days are somewhat tainted (greener grass and so on) but it seems like more and more cars are now being made with at least 4 headlights (besides the DRL's) and a great many motons are choosing to illuminate all of them.
If memory serves, in ye olde days cars only had 4 headlights if the owner went out and bought 2 more to be fitted to the bumper.

Dunno when your younger days were but there have been cars with four headlamps for a long time now. From memory the Mark x Jag(1961), Zodiac mk 3(1962), Rover 2000(1963) and Triumph 2000(1963) all had four headlamps and, apart from the Jag, were all big sellers.

Yes, but people didn't drive around with all their lights on all the time.

I think many motorists now are really pleased with the gimmicky lights on their cars and are eager to show them off.

It was Volvo started the lights on all the time and, I believe, it's a legal requirement in some Scandinavian and Baltic nations. Certainly I've been stopped and warned by the police for driving without lights on a bright sunny summers day in Poland.

The "gimmicky" lights on modern cars are better than the old ones I think. The lights on my Mercedes come on automatically when it gets dark or visibility is poor. The latter is a particularly good feature and should be compulsory as so many misguided people still fail to turn their lights on in daylight fog and mist.
The "gimmicky" lighting system also dips the lights itself - or rather adjusts the headlamp range when a vehicle approaches. This works whether the other vehicle be a car, motorbike or cyclist.
Most of the problems described here are caused by people in vehicles which don't have "gimmicky" lighting systems.

[Mick F]

Our Fiat 500 has an electric rear view mirror that automatically dims when headlights behind are too bright.
Excellent bit of kit.

It's called an Elecrochromatic Dipping Rearviw Mirror, and makes bright headlights a non-dazzling green colour. I wish all the cars I'd ever owned had one!

[shouldbeinbed]

ahem, as mentioned on page 1& to save those talking about fitting alternate mirrors and blocking the beam in other Heath Robinson ways, from a bodge too far.

If you use a magic shine or equivalent this will be the best not quite £6 you can spend for it - they really do work for you seeing the road ahead and for the poor dazzled onlooker http://www.amazon.co.uk/SEEN-ANGLE-DIFF ... and+b+seen

Ahem, without meaning to be argumentative at all, I've looked at the link above and the associated pictures, especially the two showing the beam pattern before and after fitting the diffuser. It seems to me that with the diffuser fitted the main beam covers a much wider area with 'bright light', thus increasing the probability of 'dazzling' someone in front of the light if the light down angle is not correct - no?

No....not in my experience at all, the beam pattern becomes more rectangular with the fresnel glass rather than a simple cone of light expanding out in all directions as you get with the plain glass, so yes there is a wider horizontal spread of light but at the expense of some of the vertical spread. You angle the light accordingly so it shines on the road where you want it and bob's yer uncle. If its not down angled right then it is of very little use to you as a light anyway and you'd soon fix that simple error. If you bring in ineptitude or deliberate misuse/misalignment then you can say 'surely it won't work' about absolutely anything

[thirdcrank]

shouldbeinbed

I think you have now linked to something like what I posted was needed. (Your first post didn't include that link and I wrongly thought that a Fresnel lens was simply one of those flat magnifying glasses.)

I found the Amazon reviews useful although, as usual, there are some which say nothing informative.

[shouldbeinbed]

shouldbeinbed

I think you have now linked to something like what I posted was needed. (Your first post didn't include that link and I wrongly thought that a Fresnel lens was simply one of those flat magnifying glasses.)

I found the Amazon reviews useful although, as usual, there are some which say nothing informative.

My apologies for not linking to it in the first post, my fault for assuming that these were more common knowledge & people would already know what I was on about.

They are worth a punt for a fiver (if you've got a magicshine or copy of the right glass diameter) If you do get one, when you fit it: the lines run vertical (counter intuitive to how I though they'd work, but its a long time since school physics lessons ) and put it in just slightly offset from vertical before you screw the lamp housing back together again as you'll find that the last twist to properly tighten it all up will shift the glass round slightly as the rubber seal squidges and grips it too.

[deliquium]

the beam pattern becomes more rectangular with the fresnel glass rather than a simple cone of light expanding out in all directions as you get with the plain glass, so yes there is a wider horizontal spread of light but at the expense of some of the vertical spread. You angle the light accordingly so it shines on the road where you want it and bob's yer uncle. If its not down angled right then it is of very little use to you as a light anyway and you'd soon fix that simple error. If you bring in ineptitude or deliberate misuse/misalignment then you can say 'surely it won't work' about absolutely anything

This is also my experience with the replacement Fresnel lens fitted to the Magicshine copy lamps. The modified shape of beam is excellent for road riding, as little light gets lost up in the sky or into an oncoming driver's/cyclists'/pedestrians' eyes

[cotswolds]

the beam pattern becomes more rectangular with the fresnel glass rather than a simple cone of light expanding out in all directions as you get with the plain glass, so yes there is a wider horizontal spread of light but at the expense of some of the vertical spread. You angle the light accordingly so it shines on the road where you want it and bob's yer uncle. If its not down angled right then it is of very little use to you as a light anyway and you'd soon fix that simple error. If you bring in ineptitude or deliberate misuse/misalignment then you can say 'surely it won't work' about absolutely anything

This is also my experience with the replacement Fresnel lens fitted to the Magicshine copy lamps. The modified shape of beam is excellent for road riding, as none gets lost up in the sky or into an oncoming driver's/cyclists'/pedestrians' eyes

+1 for the usefulness of these.

I projected the beam onto a wall and made some measurements and reckoned it changed the beam from a circle to a rectangle of about 5 times the width of the spot. Hardly any change in the height. Spreading the light out over a bigger area means a big reduction in peak brightness which is the main benefit for me.

I use it primarily as a running (head)torch; we have a club rule that high-viz tabards must be worn on evening runs. The light reflecting off other people's tabards was so bright that I had to turn it off and only use it if I was at the front. The lens makes it practical to leave on, and so is much more useful.

[JohnChell]

I was heading home on friday along a very dark, uphill road with gates & cattle grids, a motorcyclist pulled up along side me and said "your lights are good mate, they're brighter than mine". So we paused and compared, he was right, my front light illuminated the road further ahead than his did even on main beam.

Personally i think this is great, cars know i'm there before they even come around the corner, when they see the light they are not sure if i'm a cycle, motor cycle, or even another car with a light out, so I get lots of space and on coming traffic slows on the narrow lanes, its also fantastic for the unlit sustrans route with a former railway tunnel that i ride to work on. Even in daylight its very visable if set to strobe.

If I meet another oncomig cyclist i just turn it down to a lower setting, no complaints so far, apart from one numpty cycling in town on the footpath with no lights on who complained it was too bright. The light puts out around 3000 lumens (what ever that means) you can certainly see where you are going.

[thirdcrank]

... The light puts out around 3000 lumens (what ever that means) ...

It means it's some five times brighter than the brightest LED torch I own so I'm envious. What's the make and model?

[JohnChell]

It may well be over kill for the road, but for my very dark off road ride to work i find even the lowest setting fine most of the time - (this means I only have to charge it once a week and still get a very bright light on its lowest setting they claim a burn time of up to 36 hours, at full power its 2-3, hut the half power setting makes it as bright as most off road lights and I have used this for this for the dark hours of 24 hour events without the power indicator reaching its lowest level.) I bought it to take part in a 24 hour mtb event, but now I have it i use it year round as even in summer the unlit raiway tunnel on the local sustrans route can be very gloomy.

http://www.use1.com/exposure-lights/cyc ... x-pack-mk5