Flashing front light in daytime.

On Fri, 23 May 2008 13:03:27 +0100

Nick said:

I was stuck in traffic in my car at about 8.30 this morning looking
down at the radio to change channel. Out of my peripheral vision I
became aware of a flashing light from outside. It turned out to be a
bike filtering up the inside, some way back.

I have never thought of using a front light in daylight but was very
impressed by the result. It wasn't the brightest day this morning but
it wasn't really overcast or anything.

Funny you should mention this - I also saw a cyclist with a flashing
front light earlier today. I've never before noticed one in daylight.

Rob Morley said:

On Fri, 23 May 2008 13:03:27 +0100

Nick said:

I was stuck in traffic in my car at about 8.30 this morning looking
down at the radio to change channel. Out of my peripheral vision I
became aware of a flashing light from outside. It turned out to be a
bike filtering up the inside, some way back.

Quoted message said:

I have never thought of using a front light in daylight but was very
impressed by the result. It wasn't the brightest day this morning but
it wasn't really overcast or anything.

Funny you should mention this - I also saw a cyclist with a flashing
front light earlier today.  I've never before noticed one in daylight.

Rob Morley said:

On Fri, 23 May 2008 13:03:27 +0100

Nick said:

I was stuck in traffic in my car at about 8.30 this morning looking
down at the radio to change channel. Out of my peripheral vision I
became aware of a flashing light from outside. It turned out to be a
bike filtering up the inside, some way back.

Quoted message said:

I have never thought of using a front light in daylight but was very
impressed by the result. It wasn't the brightest day this morning but
it wasn't really overcast or anything.

Funny you should mention this - I also saw a cyclist with a flashing
front light earlier today.  I've never before noticed one in daylight.

I regularly see cyclists with flashing rear lights in poor light (well
I did through the winter). They were wasting their batteries as
without exception I could see they were there before I could tell the
light was on. Whatever light you saw must have been pretty bright to
catch your attention in your mirror.

OT: Posting via Google Groups now requires you to type in a
verification word shown in distorted characters - presumably an
attempt to reduce the spam.

Rob

Quoted message said:

Rob Morley said:

On Fri, 23 May 2008 13:03:27 +0100

Nick said:

I was stuck in traffic in my car at about 8.30 this morning looking
down at the radio to change channel. Out of my peripheral vision I
became aware of a flashing light from outside. It turned out to be a
bike filtering up the inside, some way back.
I have never thought of using a front light in daylight but was very
impressed by the result. It wasn't the brightest day this morning but
it wasn't really overcast or anything.

Funny you should mention this - I also saw a cyclist with a flashing
front light earlier today. I've never before noticed one in daylight.

I regularly see cyclists with flashing rear lights in poor light (well
I did through the winter). They were wasting their batteries as
without exception I could see they were there before I could tell the
light was on. Whatever light you saw must have been pretty bright to
catch your attention in your mirror.

It wasn't in my mirror. I was looking down at my radio, the whole inside
of my car was flashing not brightly but just enough to pick up on.

That is why I was impressed. I really wasn't paying attention to
anything but it still got through to me. To be honest my first vague
impression was that there was an emergency vehicle somewhere around.

I want one!

Nick said:

Quoted message said:

Rob Morley said:

On Fri, 23 May 2008 13:03:27 +0100

Quoted message said:

Quoted message said:

Nick <[email hidden]> wrote:
> I was stuck in traffic in my car at about 8.30 this morning looking
> down at the radio to change channel. Out of my peripheral vision I
> became aware of a flashing light from outside. It turned out to be a
> bike filtering up the inside, some way back.
> I have never thought of using a front light in daylight but was very
> impressed by the result. It wasn't the brightest day this morning but
> it wasn't really overcast or anything.
Funny you should mention this - I also saw a cyclist with a flashing
front light earlier today.  I've never before noticed one in daylight..

Quoted message said:

I regularly see cyclists with flashing rear lights in poor light (well
I did through the winter). They were wasting their batteries as
without exception I could see they were there before I could tell the
light was on. Whatever light you saw must have been pretty bright to
catch your attention in your mirror.

It wasn't in my mirror. I was looking down at my radio, the whole inside
of my car was flashing not brightly but just enough to pick up on.

That is why I was impressed. I really wasn't paying attention to
anything but it still got through to me. To be honest my first vague
impression was that there was an emergency vehicle somewhere around.

I want one!- Hide quoted text -

I think that with LEDs you can turn up the brightness of the
flash a lot as long as the duration is reduced accordingly
to maintain an acceptable average power level.
i.e. not melt it.

Could have been a Xenon strobe I suppose.

I think that research carried out for the aviation industry
years ago demonstrated that for a GIVEN POWER
CONSUMPTION flashing lights were easier to see.
Hence they now use flashers on planes. Power on
planes is expensive.

Of course the average bicycle flasher is designed not to
increase its visibility when flashing but to save power.
I certainly seem to find the average bicycle flasher
harder to spot than a non flasher and when cycling
I have ever used flash mode on any light that I have had.

On Fri, 23 May 2008 07:12:26 -0700 (PDT), [email hidden]

Quoted message said:

OT: Posting via Google Groups now requires you to type in a
verification word shown in distorted characters - presumably an
attempt to reduce the spam.

About time too!

--
(\__/) M.
(='.'=) Owing to the amount of spam posted via googlegroups and
("😉_("😉 their inaction to the problem. I am blocking most articles
posted from there. If you wish your postings to be seen by
everyone you will need use a different method of posting.
See http://improve-usenet.org

Bod43 writtificated

Quoted message said:

for a GIVEN POWER
CONSUMPTION flashing lights were easier to see.

Quoted message said:

Of course the average bicycle flasher is designed not to
increase its visibility when flashing but to save power.
I certainly seem to find the average bicycle flasher
harder to spot than a non flasher and when cycling
I have [n]ever used flash mode on any light that I have had.

Assuming the flashes are at the same brightness as the steady, wouldn't
having the light at the flashing provide both longer battery life AND
better visibility?

On Fri, 23 May 2008 07:12:26 -0700 (PDT), [email hidden]

Quoted message said:

I regularly see cyclists with flashing rear lights in poor light (well
I did through the winter). They were wasting their batteries as
without exception I could see they were there before I could tell the
light was on. Whatever light you saw must have been pretty bright to
catch your attention in your mirror.

They might not have had batteries - might be Reelights...
http://tinyurl.com/3pmmxg (Wiggle page about Reelights)

Admittedly in daylight Reelights would possibly not attract the
attention of someone not already looking in that general direction

--

John

On 24 May, 10:58, Mark T
<pleasegivegenerously@warmail*turn_up_the_heat_to_reply*.com.invalid>

Quoted message said:

Bod43 writtificated

Quoted message said:

for a GIVEN POWER
CONSUMPTION flashing lights were easier to see.
Of course the average bicycle flasher is designed not to
increase its visibility when flashing but to save power.
I certainly seem to  find the average bicycle flasher
harder to spot than a non flasher and when cycling
I have [n]ever used flash mode on any light that I have had.

Assuming the flashes are at the same brightness as the steady, wouldn't
having the light at the flashing provide both longer battery life AND
better visibility?

I have no idea.

I am pretty certain about the aviation research. Well,
certain that I read it somewhere and not in the Sun.

My own experience leads me to believe that your
suggestion is mistaken but I know that I can't
really tell without doing measurements and I have not.

Quoted message said:

I regularly see cyclists with flashing rear lights in poor light (well
I did through the winter). They were wasting their batteries as
without exception I could see they were there before I could tell the
light was on.

Which is why I built a rear light with six 1 watt Luxeon power
illuminators (after an elderly man, not wearing glasses, who probably
drove by keeping the car between the blurred green bits which were the
edge of the road, avoiding other cars by not running into any large or
illuminated blurred bit, smashed into me doing 50 mph). Testing it on
myself, from 100ft away, I can see the flash in my peripheral vision, so
hopefully it'll also draw attention from anyone not looking at the road
while driving. I was considering a xenon strobe with a red filter, but
LEDs seemed like a better bet; no mucking around with high voltages.

--
From the sunny Isle of Man.
Yes, the Reply-To email address is valid.

Dylan Smith said:

Quoted message said:

I regularly see cyclists with flashing rear lights in poor light (well
I did through the winter). They were wasting their batteries as
without exception I could see they were there before I could tell the
light was on.

Which is why I built a rear light with six 1 watt Luxeon power
illuminators (after an elderly man, not wearing glasses, who probably
drove by keeping the car between the blurred green bits which were the
edge of the road, avoiding other cars by not running into any large or
illuminated blurred bit, smashed into me doing 50 mph). Testing it on
myself, from 100ft away, I can see the flash in my peripheral vision, so
hopefully it'll also draw attention from anyone not looking at the road
while driving. I was considering a xenon strobe with a red filter, but
LEDs seemed like a better bet; no mucking around with high voltages.

I wonder what effect flash frequency has, whether to use a flicker or
something a little higher like 20Hz. If you notice that computer monitor
flicker is noticeable more in peripheral vision because peripheral
vision is designed to see changing things. This at least back when
monitors used to run at 50Hz or lower.

I find that in poor conditions, especially fog or rain, bike lights make
a huge difference.

- Richard

--
_/_/_/ _/_/_/ _/_/_/ Richard dot Corfield at gmail dot com
_/ _/ _/ _/
_/_/ _/ _/ Time is a one way street,
_/ _/ _/_/ _/_/_/ except in the Twilight Zone

On Tue, 27 May 2008 17:16:50 +0100

Richard Corfield said:

I wonder what effect flash frequency has, whether to use a flicker or
something a little higher like 20Hz.

The flash rate is legally limited because of the distraction/
epileptic fits it might cause.

Rob Morley said:

On Tue, 27 May 2008 17:16:50 +0100

Richard Corfield said:

I wonder what effect flash frequency has, whether to use a flicker or
something a little higher like 20Hz.

The flash rate is legally limited because of the distraction/
epileptic fits it might cause.

For an *obligatory* front light the flash rate is limited to 4Hz. See
paragraph 9(3):
http://www.opsi.gov.uk/si/si2005/20052559.htm

which becomes paragraph 12(c) of:
<http://www.opsi.gov.uk/si/si1989/Uksi_19891796_en_7.htm#nsch2>

For an optional front light the same requirement seems to apply (see
paragraph 10 of the 2005 SI).

--
Danny Colyer <http://www.redpedals.co.uk>
Reply address is valid, but that on my website is checked more often
"The plural of anecdote is not data" - Frank Kotsonis

Danny Colyer said:

Quoted message said:

The flash rate is legally limited because of the distraction/
epileptic fits it might cause.

For an *obligatory* front light the flash rate is limited to 4Hz. See
paragraph 9(3):
http://www.opsi.gov.uk/si/si2005/20052559.htm

between 60 and 240 times per minute, even mark/space ratio, which would
rule out some of the pretty pattern lights on the market, though I think
that paragraph was front lights.

Quoted message said:

which becomes paragraph 12(c) of:
<http://www.opsi.gov.uk/si/si1989/Uksi_19891796_en_7.htm#nsch2>

For an optional front light the same requirement seems to apply (see
paragraph 10 of the 2005 SI).

Good job I posted here then, as sometimes a 20Hz or above light would be
tempting. I thought the fitting rate peaked somewhere lower than 20Hz.
Distraction, or at least being seen, is of course the aim. Maybe something
too effective, something that held attention, would cause problems.

Presumably much higher frequency switching supplies count as continuous,
which 20Hz or a little higher would almost seem to be.

- Richard

--
_/_/_/ _/_/_/ _/_/_/ Richard dot Corfield at gmail dot com
_/ _/ _/ _/
_/_/ _/ _/ Time is a one way street,
_/ _/ _/_/ _/_/_/ except in the Twilight Zone

Richard Corfield said:

Danny Colyer said:

Quoted message said:

The flash rate is legally limited because of the distraction/
epileptic fits it might cause.

For an *obligatory* front light the flash rate is limited to 4Hz. See
paragraph 9(3):
http://www.opsi.gov.uk/si/si2005/20052559.htm

between 60 and 240 times per minute, even mark/space ratio, which would
rule out some of the pretty pattern lights on the market, though I think
that paragraph was front lights.

Sorry. I thought, from the thread header and the first post, that front
lights were the subject under discussion. I've been back and read your
post properly and see that you'd moved onto rear lights.

The same limits apply to rear lights, though, just a bit further down
the document.

--
Danny Colyer <http://www.redpedals.co.uk>
Reply address is valid, but that on my website is checked more often
"The plural of anecdote is not data" - Frank Kotsonis

Nick said:

I have never thought of using a front light in daylight but was very
impressed by the result.

I'm put in mind of a recent article in .citycycling about the use of
Hi Viz and lights. The more folks wear reflectives and use ever
bigger brighter lights the more the drivers come to expect them and
stop looking out for folks without them.

On Thu, 29 May 2008 00:57:03 -0700 (PDT)

POHB said:

Nick said:

I have never thought of using a front light in daylight but was very
impressed by the result.

I'm put in mind of a recent article in .citycycling about the use of
Hi Viz and lights. The more folks wear reflectives and use ever
bigger brighter lights the more the drivers come to expect them and
stop looking out for folks without them.

That's the same argument as has been made against compulsory daylight
running lights on cars - road users come to expect all 'hazards' to be
illuminated and are surprised[1] by anything that isn't.

[1] But not necessarily as surprised as the cyclist they just
stepped/drove out in front of.

POHB said:

Nick said:

I have never thought of using a front light in daylight but was very
impressed by the result.

I'm put in mind of a recent article in .citycycling about the use of
Hi Viz and lights. The more folks wear reflectives and use ever
bigger brighter lights the more the drivers come to expect them and
stop looking out for folks without them.

I am in favour of Hi-Viz gear, but see the point of what you are saying.
I think it would work best if everyone uses stuff like this differently.
(The theory of Big probably says this).

e.g. with lits, some people mount a flasher on the handle bars, and
other people pretend to be Daleks with a lit on their forehead.
Doing this means other road users will not expect a standard way of
lighting cyclists, and will keep a better eye out for cyclists.

Of course we all know motorists are far more adept at see stealth
cyclists than christmas trees.

Martin said:

POHB said:

Nick said:

I have never thought of using a front light in daylight but was very
impressed by the result.

I'm put in mind of a recent article in .citycycling about the use of
Hi Viz and lights. The more folks wear reflectives and use ever
bigger brighter lights the more the drivers come to expect them and
stop looking out for folks without them.

I am in favour of Hi-Viz gear, but see the point of what you are saying.
I think it would work best if everyone uses stuff like this differently.
(The theory of Big probably says this).

e.g. with lits, some people mount a flasher on the handle bars, and
other people pretend to be Daleks with a lit on their forehead.
Doing this means other road users will not expect a standard way of
lighting cyclists, and will keep a better eye out for cyclists.

Of course we all know motorists are far more adept at see stealth
cyclists than christmas trees.

For what is worth I got a look at it today. It looked a lot like an
Exposure Enduro Maxx Front Light.

http://tinyurl.com/6nrlh6

At £270.00 a little beyond my justification range.