Lights: flashing, bright: article in Cycle

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freeflow
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Re: Lights: flashing, bright: article in Cycle

Post by freeflow »

Only if Halfords and others stop selling headlight bulbs that are 40% brighter etc and manufacturers remove LED headlights which seem to produce much more glare even when they are dipped. And finally 'to advocate' is not the same as 'to instruct'.
Flinders
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Re: Lights: flashing, bright: article in Cycle

Post by Flinders »

mjr wrote:
Flinders wrote:
Pedal reflectors are fine, but my pedals don't take them. So perhaps anklets that are reflective, or have lights, would be a decent substitute if the law were to catch up with modern bike design.

I think if your pedals don't take reflectors (why isn't this part of the purchasing decision?) then if you wear yellow ankle bands of some sort, you'll all the benefit of looking pedally and almost no-one will remark upon it.


It isn't a question of whether it's part of the decision or not in my case, as I don't commute any more by bike and choose my riding times so as not to ride in the dark. I've only used lights once this last year, and that was for a very early morning start just after dawn when it was light but a bit murky, so I wanted a bit more visibility. I don't think pedal reflectors are actually much use on clipless pedals, you just wouldn't see them on mine most of the time even if they were there due to the position of my foot; I used to have them on my old clip-and-strap ones when I commuted. Anklets would be much more visible. (So I got some that are reflective and have little flashing lights at the recent Aldi sale, just in case I ever need to go out in the dark :wink: My shoes/bags have reflective bits too.)

However, as this has got me thinking about it, I've just had a search, and there do seem to be some reflectors you can get for clipless pedals. Not sure if they'd fit mine. Next time I'm in the LBS I'll ask.
De Sisti
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Re: Lights: flashing, bright: article in Cycle

Post by De Sisti »

Lance Dopestrong wrote:You will care that you dazzle others when they can't judge your speed and have you off.


Where's the evidence? Has it happened to you?
Last edited by De Sisti on 13 Oct 2014, 10:22pm, edited 1 time in total.
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[XAP]Bob
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Re: Lights: flashing, bright: article in Cycle

Post by [XAP]Bob »

De Sisti wrote:
Lance Dopestrong wrote:You will care that you dazzle others when they can't judge your speed and have you off.


Where's the evidence? Has it happened to you?


As a driver - yes, very nearly.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
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Lance Dopestrong
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Re: Lights: flashing, bright: article in Cycle

Post by Lance Dopestrong »

De Sisti wrote:
Lance Dopestrong wrote:You will care that you dazzle others when they can't judge your speed and have you off.


Where's the evidence? Has it happened to you?

Suzuki did much research into this in the 1980s. The human brain calculates an oncoming objects speed by the rate at which it grows against the background. They discovered over bright lights concealed the outline and made it difficult to judge an incoming motorbikes speed, making a T bone scenario more rather than less likely.

I use a bright but sensible light and aim it at the road surface ahead of my bike, not into the faces of incoming road users, so it's never happened to me.
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Flinders
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Re: Lights: flashing, bright: article in Cycle

Post by Flinders »

Lance Dopestrong wrote:
De Sisti wrote:
Lance Dopestrong wrote:You will care that you dazzle others when they can't judge your speed and have you off.


Where's the evidence? Has it happened to you?

Suzuki did much research into this in the 1980s. The human brain calculates an oncoming objects speed by the rate at which it grows against the background. They discovered over bright lights concealed the outline and made it difficult to judge an incoming motorbikes speed, making a T bone scenario more rather than less likely.

I use a bright but sensible light and aim it at the road surface ahead of my bike, not into the faces of incoming road users, so it's never happened to me.


Interesting, and, knowing what I do about visual things, entirely believable.
gplhl
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Re: Lights: flashing, bright: article in Cycle

Post by gplhl »

Cyclist with front lights incorrectly set and too bright put cyclists on the other side of the road at huge risk as blinding a car just about to go past a cyclist is very dangerous. It happens all too often where people only think of themselves and not other road users car and bikes alike.

I think you should be able to dip them like vehicle lights.

Gary
www.longbikeride.co.uk
beardy
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Re: Lights: flashing, bright: article in Cycle

Post by beardy »

If they were that powerful that they needed dipping then sure.

However even the really good lights are only on a par with a dipped car headlight and we almost never need the highbeam on our cars when travelling at cycling speeds.

I think it would be quite good to have lights set up in a way that fits motorcycle/car dipheadlight regs and any additional lights on an instant switch under what ever rules cover highbeam (and attached aux lights) lamps.
SA_SA_SA
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Re: Lights: flashing, bright: article in Cycle

Post by SA_SA_SA »

freeflow wrote:Only if Halfords and others stop selling headlight bulbs that are 40% brighter etc and manufacturers remove LED headlights which seem to produce much more glare even when they are dipped. ...

This may be because they are cold blue white (hence as far as you nighttime eye is concerned brighter than the lumens** rating says). There is no reason why LEDS / HIDS cannot be warmer whites like raw halogens: it seems a failure of the UN-ECE that they have not limited the blue component of headlamps. Warmer white cycle lamps would also be a good idea.

**lumens etc are based on the daylight colour sensitivity of the eye :(


I am puzzled by the claimed distance judgement issue with rear flashing lamps* :---
eg driver on dipped beam sees flashing red lamp ahead, so probably a cyclist, even assuming they are negligently and incorrectly driving faster than they can see according to their dipped beam, they should surely be slowing down and will have the distance at which the cyclists reflector(s) light up to correct any distance error, and failing that the distance at which their beam illuminates the cyclist. Is there any non-anecdotal evidence of this difficulty? I wonder if the distance judgement complaints come from the slower 1-2Hz lamps (faster is better I thought, but the legal upper limit 4Hz is quite low compared to what used to be available: I used to think 7Hz was best).
Why did the Dft not publish their evidence on flashing vs steady?


*I think bright flashing front lamps serve no purpose against their irritation factor, and should be deprecated/their legal permission phased out.


gplhl wrote:...I think you should be able to dip them like vehicle lights. ...

But BS and German approved front lamps have a dipped beam pattern by default or do you mean that cyclists should have the option of a lamp that switches between a main and dipped style beam just like motor vehicles?
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[XAP]Bob
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Re: Lights: flashing, bright: article in Cycle

Post by [XAP]Bob »

The upper limit is based on the propensity to trigger photosensitive epilepsy.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
SA_SA_SA
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Re: Lights: flashing, bright: article in Cycle

Post by SA_SA_SA »

[XAP]Bob wrote:The upper limit is based on the propensity to trigger photosensitive epilepsy.

Yes, I know that, but it still seemed lower than I expected, and IMO reduced the effectiveness of flashing lamps: were fits reported as having been triggered at 4 to 7Hz from small sources such a cycle lamps or other similar light sources? I was also puzzled by allowing <=2Hz as that is the same as turn direction indicators.
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mercalia
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Re: Lights: flashing, bright: article in Cycle

Post by mercalia »

is it me or do others here think that most CAR headlights even when dipped still dazzle? I dont think a few cycle lights make that much difference?
bogmyrtle
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Re: Lights: flashing, bright: article in Cycle

Post by bogmyrtle »

mercalia wrote:is it me or do others here think that most CAR headlights even when dipped still dazzle? I dont think a few cycle lights make that much difference?


Generally no but occasionally there will be a car with the headlights not set properly.
Some people become more sensitive to light with age. I believe increased sensitivity is particularly common in women, although not exclusively so.
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[XAP]Bob
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Re: Lights: flashing, bright: article in Cycle

Post by [XAP]Bob »

mercalia wrote:is it me or do others here think that most CAR headlights even when dipped still dazzle? I dont think a few cycle lights make that much difference?

I find most dazzling, traffic lights too (the council claim they are correctly dimming).
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
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