More on lights.

I read the recent "bright lights" posting which got me in to a bit of
research which in turn revealed that red lights are better for vision at
night as they highlight obstacles with much less depth perception issues
and, whilst highly visible to those around are much less blinding.

Does anyone then have experience using a red light for forward lighting
(illegal on the road in the UK I realise but i'd be prepared to take the
risk on quite roads), also perhaps an excellent off road option?

What about other colour options? I assume if what is said about red is
true then the longer wavelengths are superior?

On Fri, 26 Dec 2008 09:01:17 +0000, Keiron wrote:

I read the recent "bright lights" posting which got me in to a bit of
research which in turn revealed that red lights are better for vision at
night as they highlight obstacles with much less depth perception issues
and, whilst highly visible to those around are much less blinding.

This is one of those areas of research that are interesting, but for
bicycle riders in the realm of sillness.

Think about it?
White light includes red light. Why throw away 7/8ths of the light?

On Dec 26, 9:01*am, Keiron wrote:
I read the recent "bright lights" posting which got me in to a bit of
research which in turn revealed that red lights are better for vision at
night as they highlight obstacles with much less depth perception issues
and, whilst highly visible to those around are much less blinding.

Does anyone then have experience using a red light for forward lighting
(illegal on the road in the UK I realise but i'd be prepared to take the
risk on quite roads), also perhaps an excellent off road option?

What about other colour options? I assume if what is said about red is
true then the longer wavelengths are superior?

You can legally show, or at least usually get away with showing, an
amber light to the front. Or you could just throw radiation not in the
visible spectrum and use goggles to see the road. If anyone asks why
you to these weird lengths, say you're involved in secret work for the
government. -- Andre Jute

On 26 Dec 2008 13:48:05 GMT, terryc wrote:

On Fri, 26 Dec 2008 09:01:17 +0000, Keiron wrote:

I read the recent "bright lights" posting which got me in to a bit of
research which in turn revealed that red lights are better for vision at
night as they highlight obstacles with much less depth perception issues
and, whilst highly visible to those around are much less blinding.

This is one of those areas of research that are interesting, but for
bicycle riders in the realm of sillness.

Think about it?
White light includes red light. Why throw away 7/8ths of the light?

a) not all lights are white; and

b) if the improvement in perception is sufficient, it may be worth any
loss.

On Fri, 26 Dec 2008 13:48:05 +0000, terryc wrote:

On Fri, 26 Dec 2008 09:01:17 +0000, Keiron wrote:

I read the recent "bright lights" posting which got me in to a bit of
research which in turn revealed that red lights are better for vision
at night as they highlight obstacles with much less depth perception
issues and, whilst highly visible to those around are much less
blinding.

This is one of those areas of research that are interesting, but for
bicycle riders in the realm of sillness.

Think about it?
White light includes red light. Why throw away 7/8ths of the light.

Bulbs and LEDs are pretty powerful now, I suspect a decently powered red
light source could be produced, Besides it was widely stated in the
"bright light" post that brighter isn't actually better. (and what "_"
said)

Keiron wrote (in part):

Does anyone then have experience using a red light for forward
lighting (illegal on the road in the UK I realise but i'd be prepared
to take the risk on quite roads), also perhaps an excellent off road
option?


http://comics.com/frank&ernest/2008-12-21/

HTH!

On Fri, 26 Dec 2008 06:14:06 -0800, Andre Jute wrote:

On Dec 26, 9:01Â*am, Keiron wrote:
I read the recent "bright lights" posting which got me in to a bit of
research which in turn revealed that red lights are better for vision
at night as they highlight obstacles with much less depth perception
issues and, whilst highly visible to those around are much less
blinding.

Does anyone then have experience using a red light for forward lighting
(illegal on the road in the UK I realise but i'd be prepared to take
the risk on quite roads), also perhaps an excellent off road option?

What about other colour options? I assume if what is said about red is
true then the longer wavelengths are superior?

You can legally show, or at least usually get away with showing, an
amber light to the front. Or you could just throw radiation not in the
visible spectrum and use goggles to see the road. If anyone asks why you
to these weird lengths, say you're involved in secret work for the
government. -- Andre Jute

haha. That had occured to me although steaming through the streets or
wood at night on a bike is probably not all that covert, a requisite for
secret government work i'd suggest.
But truly, it was consideration as my current lighting research is in
preparation for touring with an element of stealth camping where such bit
of kits would doubtless prove useful. But god knows what infra red
emitters are available or even if it would work.

Keiron wrote:
On Fri, 26 Dec 2008 13:48:05 +0000, terryc wrote:

On Fri, 26 Dec 2008 09:01:17 +0000, Keiron wrote:

I read the recent "bright lights" posting which got me in to a bit of
research which in turn revealed that red lights are better for vision
at night as they highlight obstacles with much less depth perception
issues and, whilst highly visible to those around are much less
blinding.
This is one of those areas of research that are interesting, but for
bicycle riders in the realm of sillness.

Think about it?
White light includes red light. Why throw away 7/8ths of the light.

Bulbs and LEDs are pretty powerful now, I suspect a decently powered red
light source could be produced, Besides it was widely stated in the
"bright light" post that brighter isn't actually better. (and what "_"
said)

Also a red light used as a headlamp could give misleading information to
other road users, because that color is reserved for the rear of a vehicle.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

On Fri, 26 Dec 2008 07:51:28 -0800, Bill Sornson wrote:

Keiron wrote (in part):

Does anyone then have experience using a red light for forward lighting
(illegal on the road in the UK I realise but i'd be prepared to take
the risk on quite roads), also perhaps an excellent off road option?


http://comics.com/frank&ernest/2008-12-21/

HTH!

Haha. I imagine my influence with the police will be less than santa's
too.

terryc wrote:
On Fri, 26 Dec 2008 09:01:17 +0000, Keiron wrote:

I read the recent "bright lights" posting which got me in to a bit of
research which in turn revealed that red lights are better for vision at
night as they highlight obstacles with much less depth perception issues
and, whilst highly visible to those around are much less blinding.

This is one of those areas of research that are interesting, but for
bicycle riders in the realm of sillness.

Think about it?
White light includes red light. Why throw away 7/8ths of the light?

The human eye has rod & cone cells. The rod cells are much more numerous
and 100x more sensitive to light, but they do not distinguish color. The
rod cell response peaks in the blue-green wavelengths, and is virtually
non-existent in reds. Rods give us our night vision, but cone cells give
us color and detail perception.

Some DIY bike light makers have deliberately used blue-green LED's
claiming a many-fold increase in actual perceived brightness. Sounds
good in theory. Red light can be used to preserve night vision because
night vision is insensitive to it. Red bike lights for illumination of
the road would seem to be a poor idea. Off-road, they'd make foliage
look very dark, another disadvantage.

You don't have to "throw away" light with modern LED lamps. LEDs are
quantum devices which naturally emit at a narrow wavelength. White LEds
are typically made by either blending light from multiple monochrome
LEDs or by exiting a blend of phosphors with a monochrome LED.

A monochrome blue-green LED certainly seems more efficient overall when
factoring the spectral sensitivity of the eye.