Adaptive Headlights

If the OP wanted to know if the Adaptive headlights were worthwhile enough
to order as an option, then yes, it will much cheaper, $800 now than later.
You will also get self leveling, and high pressure washers.

Once the color temp gets above 5K deg K It tends to be blue. Old human eyes
don't see blue very well. IMO, anything > 5K is really a waste of money. I
have had several HID sets at 4300 and it was a very pure white light. If I
remember correctly, daylight is 4700K?

In article >,
Fred W > wrote:
> Are you sure about that Dave? I thought I had read somewhere that the
> eye is *less* responsive to blue light than longer wavelengths,
> especially yellow. OTOH, I also know the eye is also not very sensitive
> to red light considering that is the color used in "night rigging" ships
> to maintain better night vision of the crew. Perhaps the eye's
> sensitivity drops off at both ends of the spectrum?

It's most sensitive to green of the three primaries. But more sensitive at
the blue than red end - at either side of the roughly centre green.
We're used to tungsten filament lamps being towards the red end of
daylight - which is probably why many HID types look blue in comparison.
If all lights were HID of the same colour temperature they'd soon look the
norm.

--
*A fool and his money are soon partying *

Dave Plowman London SW
To e-mail, change noise into sound.

In article >,
Jim > wrote:
> No, human eyes are more sensitive to green that to either red or blue.
> There are lots and lots of references, but really this newsgroup is
> about cars not eyes.

Surely it's fair enough to discuss car lighting, and how that interfaces
with the eye/brain combination?

And I'm certainly not in favour of 'any colour' lights were it's simply a
fashion. But feel high efficiency discharge types will be the way forward
- as well as LED for low powered applications. Increasing the efficiency
of car lighting reduces cable weight and energy consumption, as well as
hopefully safety, and anything which does this can't be all bad.

--
*The problem with the gene pool is that there is no lifeguard *

Dave Plowman London SW
To e-mail, change noise into sound.

In article >,
Fred W > wrote:
>Dave Plowman (News) wrote:
>
>> Discharge lamps of the type used on cars can be any colour temperature you
>> want. However, the eye is more sensitive towards the blue end of the
>> spectrum than it is to the red, so 'red' halogen lamps don't really make
>> sense.
>
>Are you sure about that Dave? I thought I had read somewhere that the
>eye is *less* responsive to blue light than longer wavelengths,
>especially yellow. OTOH, I also know the eye is also not very sensitive
>to red light considering that is the color used in "night rigging" ships
>to maintain better night vision of the crew. Perhaps the eye's
>sensitivity drops off at both ends of the spectrum?

The eye is most sensitive to green. This is why most fluorescent tubes spike
in the green portion of the specturm - they look brighter. This is why they
show up as green on regular film. They ARE more green, but your eyes normalizes
the light and it looks "normal" when you're used to them.

The longer the wavelength of light the less is scatters in fog. This is why
fog lamps are yellow and why backscatter with blue halogens in inclement
conditions is becoming increasingly of concern to NHTSA.

Expect to see more white HID lamps. Blue is like, so passe now :-)

Note also those blue incandescent bulbs sold as fake HID's are flat out illegal,
the only legal front facing bulbs are white and yellow.

Check your local lighting regulations. They are, if nothing else, worth a laugh.

--
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
1970 280SE, 72 280SE | Home pages: http://rs79.vrx.net
633CSi 250SE/C 300SD | http://aquaria.net http://killi.net

In article >,
Richard Sperry > wrote:
>If the OP wanted to know if the Adaptive headlights were worthwhile enough
>to order as an option, then yes, it will much cheaper, $800 now than later.
>You will also get self leveling, and high pressure washers.
>
>Once the color temp gets above 5K deg K It tends to be blue. Old human eyes
>don't see blue very well. IMO, anything > 5K is really a waste of money. I
>have had several HID sets at 4300 and it was a very pure white light. If I
>remember correctly, daylight is 4700K?

Tropical daylight at noon on the equator is 5000K. Northern climates,
at noon are 7500K. The more north you go the bluer it is.



--
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
1970 280SE, 72 280SE | Home pages: http://rs79.vrx.net
633CSi 250SE/C 300SD | http://aquaria.net http://killi.net

In article >,
Dave Plowman (News) > wrote:
>In article >,
> Jim > wrote:
>
>Surely it's fair enough to discuss car lighting, and how that interfaces
>with the eye/brain combination?

This is usenet. Everything is fair.

>And I'm certainly not in favour of 'any colour' lights were it's simply a
>fashion. But feel high efficiency discharge types will be the way forward

That's pretty naive in my opinion. Nothing could be easier than incandescents.
You apply voltage to two pins and they make light. They're cheap.

HIDs ARE great, but, they have a lot of problems with automotive applications:
they don't come on instanly and a lot has to be done to get around this. They
require weird voltages and an extra large striking voltage. They're expensive
and complicated. They are however more efficient so you get the same light from
less voltage and that's important. They're not THAT much brighter, they just
look brighter because of the color of the light. When a "lamp driver module"
is one small cheap chip (a ways off yet) and all the costs have come down they're
probably be near-ubiquotous, but that's at least a decade off IMO.

>- as well as LED for low powered applications. Increasing the efficiency
>of car lighting reduces cable weight and energy consumption, as well as
>hopefully safety, and anything which does this can't be all bad.

LED"s are good but they're a point source that doesn't radiate like a coaxial
incandescent filamwnt so they have their own set of problems. WHat would be
neat is a "filamnt" in a bulb, the same shape as a regular incandescent filament
but works like an LED not a thing that burns white hot when voltage is applied.



--
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
1970 280SE, 72 280SE | Home pages: http://rs79.vrx.net
633CSi 250SE/C 300SD | http://aquaria.net http://killi.net

In article >,
Dave Plowman (News) > wrote:
>In article >,
>They can only be used with main beam - and on most cars main beam is
>already fine. It's dip that is the difficult one, and in a crowded country
>like the UK you spend most of your time using that even on the open road
>due to oncoming traffic.

So you want brighter low-beams? Uh... it's a bit of a contradiction to
want to light up the road better but nor blind the guy in front or the
guy coming the other way.

>Currently, the most efficient HID lamps do look blue compared to halogen.
>But are in fact closer to daylight.

Daylight is blue. The sky is blue not yellow.

>> "brighter" than what? I've got some Marchals halogens here than will
>> melt the bumper of the car in front of you if you get too close, to say
>> nothing of the Cibie CSR's.
>
>You can have HID lamps of near any power - same as halogens. Film lighting
>have been using them for years with sizes in the killowatts.

Sure, and GE make a 10 kilowatt carbon arc lamp for lighthouses but we're talking
car bulbs here.

>> Also, blue reflects the short wavelenghts so in cloudy/foggy conditions
>> (how RARE in merry 'old) they're the last thing you want. Effectove
>> "fog" lamps are yellow, not blue.
>
>You'll find as many opinions on the best colour for fogs as you will fogs
>themselves - but most are now just plain old halogen. It's the beam
>pattern that gives the best results.

It's not an opinion that you can see bettwe in fog with yellow light. Or
why shooting glasses for foggy says have yellow lenses.

>> I'm just not sold on HID lamps. Too expensive, too useless around here -
>> which is almost as foggy as ukkers.
>
>Then you really need custom foglamps. Which could use an HID lamp.

Other than the fact none exists, sounds swell.


--
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
1970 280SE, 72 280SE | Home pages: http://rs79.vrx.net
633CSi 250SE/C 300SD | http://aquaria.net http://killi.net

In article >,
Richard Sexton > wrote:
> >And I'm certainly not in favour of 'any colour' lights were it's simply
> >a fashion. But feel high efficiency discharge types will be the way
> >forward

> That's pretty naive in my opinion.

Really?

> Nothing could be easier than incandescents. You apply voltage to two
> pins and they make light. They're cheap.

Well just about everything on a car has moved on with improving technology.
Or perhaps you want to go back to points ignition? That's cheap too. As is
a nice single downdraught carb.

> HIDs ARE great, but, they have a lot of problems with automotive
> applications: they don't come on instanly and a lot has to be done to
> get around this.

Err, how often does it get dark suddenly? I've never found the time they
take to get to full output a problem.

> They require weird voltages and an extra large striking
> voltage. They're expensive and complicated.
They *sell* for much more. But then so does everything when it's new.

> They are however more efficient so you get the same light from less
> voltage and that's important.

Actually, less current.

> They're not THAT much brighter, they just look brighter
> because of the color of the light.

They produce approximately three times the light for the same current -
not difficult since incandescent lamps are incredibly inefficient.

> When a "lamp driver module" is one small cheap chip (a ways off yet) and
> all the costs have come down they're probably be near-ubiquotous, but
> that's at least a decade off IMO.

> >- as well as LED for low powered applications. Increasing the
> >efficiency of car lighting reduces cable weight and energy consumption,
> >as well as hopefully safety, and anything which does this can't be all
> >bad.

> LED"s are good but they're a point source that doesn't radiate like a
> coaxial incandescent filamwnt so they have their own set of problems.

For things like tail lights etc you don't need omni directional radiation
- indeed this just means you have to add some form of reflector.

> WHat would be neat is a "filamnt" in a bulb, the same shape as a regular
> incandescent filament but works like an LED not a thing that burns white
> hot when voltage is applied.

For many applications around the car, filament or point source lamps are
anything but ideal. Interior lighting for example would be better with
large soft sources. As would most other lights apart from headlamps. We're
simply used to filament lamps - that's all.

--
*Upon the advice of my attorney, my shirt bears no message at this time

Dave Plowman London SW
To e-mail, change noise into sound.

In article >,
Richard Sexton > wrote:
> >Currently, the most efficient HID lamps do look blue compared to
> >halogen. But are in fact closer to daylight.

> Daylight is blue.

No it's not. By definition.

> The sky is blue not yellow.

So the sun is blue? That's what provides daylight - not the sky.

--
*Drugs may lead to nowhere, but at least it's the scenic route *

Dave Plowman London SW
To e-mail, change noise into sound.

In article >,
Dave Plowman (News) > wrote:
>In article >,
> Richard Sexton > wrote:
>> >And I'm certainly not in favour of 'any colour' lights were it's simply
>> >a fashion. But feel high efficiency discharge types will be the way
>> >forward
>
>> That's pretty naive in my opinion.
>
>Really?

Really. That's my opinion. It's not a fact and reasonable people disagree
all the time. I'm listening.

>> Nothing could be easier than incandescents. You apply voltage to two
>> pins and they make light. They're cheap.
>
>Well just about everything on a car has moved on with improving technology.
>Or perhaps you want to go back to points ignition? That's cheap too. As is
>a nice single downdraught carb.

No. We're talking about lights here.

>> HIDs ARE great, but, they have a lot of problems with automotive
>> applications: they don't come on instanly and a lot has to be done to
>> get around this.
>
>Err, how often does it get dark suddenly? I've never found the time they
>take to get to full output a problem.

Well, YOU haven't had a problem but the fact remains, with incandescents
when you turn on the switch you get full brightness immediately. There's
a non-zero chance this will be a problem somewhere sometime.

>> They require weird voltages and an extra large striking
>> voltage. They're expensive and complicated.
>
>They *sell* for much more. But then so does everything when it's new.

I know why, I'm just pointing out it falls in the "con" not "pro" column.

>> They are however more efficient so you get the same light from less
>> voltage and that's important.
>
>Actually, less current.

True. Less energy what what I meat to say and module some teenager
pranging in my ear I actually might have.

>> They're not THAT much brighter, they just look brighter
>> because of the color of the light.
>
>They produce approximately three times the light for the same current -
>not difficult since incandescent lamps are incredibly inefficient.

Understood, but incandcents, using more energy yield very close to
the same light, and advanced ones lke CSR's put out more light than
HIDs.

>For things like tail lights etc you don't need omni directional radiation
>- indeed this just means you have to add some form of reflector.

No and no. You need to check lighting regulations and yo're guessing
(wrongly) about the reflector.

>For many applications around the car, filament or point source lamps are
>anything but ideal. Interior lighting for example would be better with
>large soft sources. As would most other lights apart from headlamps. We're
>simply used to filament lamps - that's all.

Well, I've tried LED's inside. Worthless. You go try it ane lemme know
what you think. Luxeons are nice ones to play with.



--
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
1970 280SE, 72 280SE | Home pages: http://rs79.vrx.net
633CSi 250SE/C 300SD | http://aquaria.net http://killi.net