Flashing LEDs to be made legal

[Peter B]

"Peter B" <[email protected]> wrote in message
news:[email protected]...

> And then there are those whom I suspect are visually impaired.

What I meant was they have impaired vision, I don't imagine unattractive
people are neccessarily less likely to see a cyclist ;-)

Pete

 

[Zog The Undeniable]

Peter B wrote:

> And I should have added that when I'm using higher powered front lamps
> motorists waiting to emerge from side roads seem more cautious and those
> approaching on unlit roads normally dip their lights.

I was getting flashed to dip my light (not technically possible) the
other night, and I only have a 3W dynamo lamp!

 

[Zog The Undeniable]

Alan J. Wylie wrote:

> There has been some interesting research done on this, by Dr. Daniel
> Simons of the University of Illinois, Dr. Christopher Chabris of
> Harvard University and Dr. Daniel Levin of Vanderbilt University.
>
> Google cache of Daily Telegraph article:
> <http://64.233.183.104/search?q=cache:BVGr-2MSRmgJ:www.telegraph.co.uk/connected/main.jhtml>
>
> Volunteers were asked to watch a video of a basketball game, and count
> the passes made. Whilst concentrating on this, they were oblivious to
> a woman dressed in a gorilla suit wandering across the court.

This is a slightly more basic example (warning - not safe for work).

http://www.ibogleif.dk/uk/

 

[Helen Deborah Vecht]

James Annan <[email protected]>typed


> Is SMIDSY to do with not noticing someone,

Often, sometimes despite cyclist wearing a 'cloak of invisibility'
(Brighter than Blackpool Illuminations)

> or not being able to accurately position someone
Occasionally...


> or something else entirely?
Lack of perceived threat. Impersonating Police can be very effective ;=))

--
Helen D. Vecht: [email protected]
Edgware.

 

[Simon Brooke]

in message <BE2AC21F.8FA1%[email protected]>, David Martin
('[email protected]') wrote:

> On 5/2/05 12:12 am, in article [email protected]cart,
> "Jon Rogers" <[email protected]> wrote:
>
>> On 2005-02-05, Danny Colyer <[email protected]> wrote:
>>>
>>> I'd object quite strongly to any proposal to legalise the use of
>>> flashing lights on their own.
>>
>> Why? They seem to me to be much more visible than steady lights,
>> either LED or filament lamp types.
>
> You'd actually be wrong. They are much harder to place spatially. Yes
> you know there is something there, but cannot tell exactly where it
> is.

That's like the naked streets thing. You know there is something there
but are not absolutely certain where it is, so you _slow_ _down_ and
_take_ _more_ _care_. It seems to me that's an unalloyed Good Thing.

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

For office use only. Please do not write or type below this line.

 

[Danny Colyer]

I wrote:
>>I've responded to you making that comment before. I find it very much
>>easier to track the movement of a steady light. If I know that
>>there's a cyclist ahead of me then I like to know where he is, so
>>that I can make sure I don't hit him. That's easier if he doesn't
>>keep disappearing and then reappearing somewhere else. As Peter B
>>wrote, it's a subjective matter.

and Nigel Cliffe wrote:
> Its not a subjective matter.... its a function of how the human visual
> system works. And the arguments presented in the thread as to which people
> prefer seem to back that.
<big snip>
> - Nigel (university studies included the mechanisms of human perception)

I can't think of anything much more subjective than perception!

I don't disagree with any of your points, except for the statement that
it's not a subjective matter. I think the following point made by Tony
Raven may be very relevant here:

> Spotters are taught not to intently look for things but to let
> their gaze wander. The more you concentrate on one thing, the higher
> the priority a background task has to become before its noticed.

I learnt to do that long before I learnt to drive. When driving,
cycling or walking I always let my gaze wander, rather than looking
intently for hazards. Tony's comment tells me that a lot of people
probably don't do that. That may explain why some people prefer
flashing lights (giving priority to something that attracts their
attention), while I prefer a steady light (giving priority to something
that allows me to maintain a fix on the cyclist while still enabling me
to keep scanning for other hazards).

--
Danny Colyer (the UK company has been laughed out of my reply address)
<URL:http://www.speedy5.freeserve.co.uk/danny/>
"He who dares not offend cannot be honest." - Thomas Paine

 

[Danny Colyer]

Pete Biggs wrote:
> The driver can locate and track the cyclist by means other than the
> cyclist's lights. Street lights illuminate the rider well enough on urban
> streets and the driver's headlights on unlit roads.

On an unlit road a bike light can be visible well outside the beam of
car headlights, especially if the driver has his headlights dipped
because someone is coming the other way. Personally I'd much rather see
a cyclist (or be seen, as a cyclist) 300 yards ahead than 100 yards
ahead. And having seen, or been seen, I want to be able to track the
cyclists movements, or for the driver behind me to be able to track my
movements.

--
Danny Colyer (the UK company has been laughed out of my reply address)
<URL:http://www.speedy5.freeserve.co.uk/danny/>
"He who dares not offend cannot be honest." - Thomas Paine

 

[Danny Colyer]

Velvet wrote:
>>I'd have to agree with that too, steady PLUS flashing is good,
>>flashing on own is very BAD, when you might only get a couple of
>>glimpses due to traffic, in those glimpses it is all too possible
>>that the light is in the 'off' cycle of the flash pattern.

to which Pete Biggs responded:
> That particular problem solved by using a *fast*-flashing light, one that
> flashes a few times per second.

Yeah, and gives the poor sod behind a stinking headache, thus greatly
reducing his ability to concentrate.

--
Danny Colyer (the UK company has been laughed out of my reply address)
<URL:http://www.speedy5.freeserve.co.uk/danny/>
"He who dares not offend cannot be honest." - Thomas Paine

 

[Al C-F]

On Sat, 05 Feb 2005 21:04:11 +0000, Danny Colyer
<[email protected]> wrote:

>I've responded to you making that comment before. I find it very much
>easier to track the movement of a steady light.

But you've got to notice it first, against the background of all the
other 'clutter'.

> If I know that there's
>a cyclist ahead of me then I like to know where he is, so that I can
>make sure I don't hit him. That's easier if he doesn't keep
>disappearing and then reappearing somewhere else. As Peter B wrote,
>it's a subjective matter.
>
>I don't particularly object to the use of flashing lights [1], but I
>*do* object to the lack of a steady light.

Don't the cyclists use reflectors near where you live? Or have your
headlamps broken?

 

[Al C-F]

On Sat, 5 Feb 2005 22:25:42 -0000, "Nigel Cliffe" <[email protected]>
wrote:

>Its not a subjective matter.... its a function of how the human visual
>system works. And the arguments presented in the thread as to which people
>prefer seem to back that.

I'd guess that detection of a flashing target by the human eye is
similar to the models developed by Marcum and Swerling for the radar
world.

 

[Al C-F]

On Sun, 6 Feb 2005 10:39:21 +0100, "Peter B" <[email protected]>
wrote:

>
>My brother and I have both been struck on quiet roads with good sight lines
>in perfect daylight visibility, as well as the usual near misses, so there
>are no guarantees.

I wonder:

If you are well lit, you are visible from a great distance away and
therefore you share the motorists attention with everything else he
can see, right up to the point where he passes you and you are
forgotten. His attention is never focussed on you, he is merely aware
of your presence.

If you are a stealth cyclist, at the point you emerge from the murk
you occupy all of the motorists attention to the exclusion of all else
by benefitting from the element of surprise. So at the point you are
passed, the motorist is concentrating on nothing except avoiding you.
This could be a good thing for you.

 

[Al C-F]

On Sun, 06 Feb 2005 11:20:51 GMT, Velvet <[email protected]>
wrote:

>I'd have to agree with that too, steady PLUS flashing is good, flashing
>on own is very BAD, when you might only get a couple of glimpses due to
>traffic, in those glimpses it is all too possible that the light is in
>the 'off' cycle of the flash pattern.

How slowly do your lights flash? My Vistalights would be hard to
miss, flashing or constant.

 

[Pete Biggs]

Danny Colyer wrote:
> Pete Biggs wrote:
>> The driver can locate and track the cyclist by means other than the
>> cyclist's lights. Street lights illuminate the rider well enough on
>> urban streets and the driver's headlights on unlit roads.
>
> On an unlit road a bike light can be visible well outside the beam of
> car headlights, especially if the driver has his headlights dipped
> because someone is coming the other way.

Of course, and a good flashing light is visible.............

> Personally I'd much rather see
> a cyclist (or be seen, as a cyclist) 300 yards ahead than 100 yards
> ahead. And having seen, or been seen, I want to be able to track the
> cyclists movements, or for the driver behind me to be able to track my
> movements.

Instead of being able to track so easily from 300 yards, you could be more
careful and slow down until you are close enough for your headlights to
light up the cyclist. I reckon this does actually happen.

~PB

 

[Velvet]

Al C-F wrote:
> On Sun, 06 Feb 2005 11:20:51 GMT, Velvet <[email protected]>
> wrote:
>
>
>>I'd have to agree with that too, steady PLUS flashing is good, flashing
>>on own is very BAD, when you might only get a couple of glimpses due to
>>traffic, in those glimpses it is all too possible that the light is in
>>the 'off' cycle of the flash pattern.
>
>
> How slowly do your lights flash? My Vistalights would be hard to
> miss, flashing or constant.

Dunno. Not that slowly, but when I've been a driver, I've found it
easier to spot a cyclist from further in my peripheral vision with a
flashing light, but a lot harder to judge closing speed/distance with
ONLY a flashing light.

And with other traffic around, yes, I've frequently missed the
flashing-only cycle lights simply because of the coincidence of my gaze
flicking away briefly in quick succession (as can be necessary if you're
using mirrors etc). I don't gaze for seconds at a time in my mirrors,
preferring a quick flick back and forth to monitor a potential situation
behind (imminent dangerous overtaking attempt etc), and it's in that
sort of situation that it's very possible for it to coincide with light
being on but masked by other objects, light being off and otherwise
visible, and light being on but me glancing in said mirror.

Some lights do flash rapidly, others do not. IME a steady light will
let you judge closing speed and distance well, and is visible from
further away than a reflector. Also, reflectors don't work well if you
headlight beam isn't lighting them, due to a bend in the road! Flashing
is good for attracting attention.

BUT! Flashing can be too attention-attracting, which is something else
I tend to find if there's no static accompanying them. Because you can
only judge the speed/distance in the instant the light is ON, you have
to spend more time looking at it in order to complete that judgement.


--


Velvet

 

[Pete Biggs]

Danny Colyer wrote:

>> That particular problem solved by using a *fast*-flashing light, one
>> that flashes a few times per second.
>
> Yeah, and gives the poor sod behind a stinking headache, thus greatly
> reducing his ability to concentrate.

I doubt they really do that, but cause some annoyance. It's an
unfortunate price that has to be paid until super-bright steady lights are
more practical and affordable for all cyclists all the time. We are
getting there with new generations of LED & battery technology so maybe
blinkies will die out.

~PB

 

[Pete Biggs]

Al C-F wrote:

>> I don't particularly object to the use of flashing lights [1], but I
>> *do* object to the lack of a steady light.
>
> Don't the cyclists use reflectors near where you live? Or have your
> headlamps broken?

That's a good point. Reflectors aren't as good as lights because they're
visible from more limited angles but they do count as a steady "light" to
some extent (as far as this argument goes). Same (but better) with
reflective clothing. A driver can track all that even if having trouble
with flashing lights.

~PB

 

[David Martin]

On 6/2/05 5:12 pm, in article
[email protected], "Simon Brooke"
<[email protected]> wrote:

> in message <BE2AC21F.8FA1%[email protected]>, David Martin
> ('[email protected]') wrote:
>
>> On 5/2/05 12:12 am, in article [email protected]cart,
>> "Jon Rogers" <[email protected]> wrote:
>>
>>> On 2005-02-05, Danny Colyer <[email protected]> wrote:
>>>>
>>>> I'd object quite strongly to any proposal to legalise the use of
>>>> flashing lights on their own.
>>>
>>> Why? They seem to me to be much more visible than steady lights,
>>> either LED or filament lamp types.
>>
>> You'd actually be wrong. They are much harder to place spatially. Yes
>> you know there is something there, but cannot tell exactly where it
>> is.
>
> That's like the naked streets thing. You know there is something there
> but are not absolutely certain where it is, so you _slow_ _down_ and
> _take_ _more_ _care_. It seems to me that's an unalloyed Good Thing.

Might be true for you, it isn't generally true. Naked streets is a different
concept. You know there will be conflicts and deal with them appropriately.
With a flashing light it is something different. You are more aware of
cyclists and the relevant issues. To many others it is something new and
they will react once they have clearly established what and where.

I'd liek them to establish what and where a little sooner, especially when
they are like the idiot who killed himself and three of his friends on my
local TT course by rolling his car into a field on a gentle bend.

...d

 

[Danny Colyer]

I wrote:
>>I've responded to you making that comment before. I find it very much
>>easier to track the movement of a steady light.

Al C-F wrote:
> But you've got to notice it first, against the background of all the
> other 'clutter'.

Although a flashing light is slightly more noticeable, the benefit over
a steady light is small. Returning to the subjectivity of perception,
this is the way *I* perceive the world. It is useful for me to know
that others find a flashing light very much easier to spot than a
flashing light, because it tells me that it is useful to have a flashing
light in addition to my steady light.

Having spotted the light, the presence of a steady light makes a huge
difference to my ability to track the movement. Cyclists who don't
perceive any particular benefit when seeing a steady light on a bike
should find it useful to know that I (and others) perceive a huge
benefit, because it tells them that it is useful to have a steady light
in addition to their flashing light.

>>I don't particularly object to the use of flashing lights [1], but I
>>*do* object to the lack of a steady light.
>
> Don't the cyclists use reflectors near where you live? Or have your
> headlamps broken?

IME bikes without lights often also lack reflectors. For those that
*do* have reflectors the first I see of them is usually the reflection
from my 20W Lumicycle beam. Of course, they only need to go round a
slight bend and the reflector is no longer in my headlight beam, so they
disappear. In many cases a decent steady rear light would still be visible.

I drive very, very seldom, but my observations as a motorist match those
as a cyclist.

Regardless of the quality of *my* headlights, I would not trust my
safety to the assumption that all the motorists who come up behind me
have properly adjusted and functioning headlights. Do you?

--
Danny Colyer (the UK company has been laughed out of my reply address)
<URL:http://www.speedy5.freeserve.co.uk/danny/>
"He who dares not offend cannot be honest." - Thomas Paine

 

[Danny Colyer]

I wrote:
>> Personally I'd much rather see
>>a cyclist (or be seen, as a cyclist) 300 yards ahead than 100 yards
>>ahead. And having seen, or been seen, I want to be able to track the
>>cyclists movements, or for the driver behind me to be able to track my
>>movements.

and Pete Biggs responded:
> Instead of being able to track so easily from 300 yards, you could be more
> careful and slow down until you are close enough for your headlights to
> light up the cyclist. I reckon this does actually happen.

*I* do. I am not going to assume that all of the motorists I encounter
when riding after dark will also do so. And regardless of how fast or
slow I might be going, I would still rather be able to track the
movement of a cyclist ahead of me for as long as possible before passing
him.

--
Danny Colyer (the UK company has been laughed out of my reply address)
<URL:http://www.speedy5.freeserve.co.uk/danny/>
"He who dares not offend cannot be honest." - Thomas Paine

 

[Danny Colyer]

Pete Biggs and I between us wrote:
>>>That particular problem solved by using a *fast*-flashing light, one
>>>that flashes a few times per second.
>>
>>Yeah, and gives the poor sod behind a stinking headache, thus greatly
>>reducing his ability to concentrate.
>
> I doubt they really do that, but cause some annoyance.

Do you really doubt that fast flashing lights give me a headache? I
assure you that they do (if they're bright enough to actually be of any
practical use), and if they give me a headache then it seems reasonable
to assume that they will give headaches to at least some other people.

> It's an
> unfortunate price that has to be paid until super-bright steady lights are
> more practical and affordable for all cyclists all the time. We are
> getting there with new generations of LED & battery technology so maybe
> blinkies will die out.

I seriously doubt it. All we get with improved technology is brighter
flashing lights and worse headaches.

--
Danny Colyer (the UK company has been laughed out of my reply address)
<URL:http://www.speedy5.freeserve.co.uk/danny/>
"He who dares not offend cannot be honest." - Thomas Paine