LED Lightbulbs

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Michael Chare

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Apr 13, 2012, 2:21:43 PM4/13/12
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I see I can now buy a 60W equivalent LED light bulb Philips myAmbiance
872790091840300 at a price which will take the best part of £40.00!

Are they any good?

I have also seen LED car stop & tail bulbs. Should I get one the next
time a bulb fails?

--
Michael Chare

Dave Plowman (News)

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Apr 13, 2012, 2:36:02 PM4/13/12
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In article <RpidnTRYB6M28xXS...@brightview.co.uk>,
Michael Chare <mUNDERSCOREnews@chareDOTorgDOTuk> wrote:
> I have also seen LED car stop & tail bulbs. Should I get one the next
> time a bulb fails?

Check if they carry the E mark - as all suitable replacements must do to
meet the regs. You'll likely find they don't.

--
*Any connection between your reality and mine is purely coincidental

Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.

Andrew Gabriel

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Apr 13, 2012, 3:15:44 PM4/13/12
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In article <RpidnTRYB6M28xXS...@brightview.co.uk>,
Michael Chare <mUNDERSCOREnews@chareDOTorgDOTuk> writes:
> I see I can now buy a 60W equivalent LED light bulb Philips myAmbiance
> 872790091840300 at a price which will take the best part of £40.00!
>
> Are they any good?

I would start with a very large dose of scepticism, based on past
experience of Philips (and others) claims for performance of new
lamp technologies.

I wouldn't spend £40 to find out, but if someone gave me one,
I'd certainly kick the tyres. The datasheet shows how much better
it is than a 60W filament lamp, but it's got to be very significantly
better than a £2 15W CFL before it's viable in my eyes, and it
isn't. When it costs a quarter of the current price, I would buy
one to try.

Being dimmable is interesting, but most light dimmers won't work
with such a low load, so that's probably not useful unless you have
lots of them.

> I have also seen LED car stop & tail bulbs. Should I get one the next
> time a bulb fails?

Only if the car manufacturer states they still meet the regs, which
they almost certainly will not unless they're original equipment.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Moonraker

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Apr 14, 2012, 6:32:59 AM4/14/12
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On 13/04/2012 20:15, Andrew Gabriel wrote:
> In article<RpidnTRYB6M28xXS...@brightview.co.uk>,
> Michael Chare<mUNDERSCOREnews@chareDOTorgDOTuk> writes:
>> I see I can now buy a 60W equivalent LED light bulb Philips myAmbiance
>> 872790091840300 at a price which will take the best part of £40.00!
>>
>> Are they any good?
>
> I would start with a very large dose of scepticism, based on past
> experience of Philips (and others) claims for performance of new
> lamp technologies.
>
> I wouldn't spend £40 to find out, but if someone gave me one,
> I'd certainly kick the tyres. The datasheet shows how much better
> it is than a 60W filament lamp, but it's got to be very significantly
> better than a £2 15W CFL before it's viable in my eyes, and it
> isn't. When it costs a quarter of the current price, I would buy
> one to try.
>
> Being dimmable is interesting, but most light dimmers won't work
> with such a low load, so that's probably not useful unless you have
> lots of them.
>
>> I have also seen LED car stop& tail bulbs. Should I get one the next
>> time a bulb fails?
>
> Only if the car manufacturer states they still meet the regs, which
> they almost certainly will not unless they're original equipment.
>
I read recently that LEDs in cars are not as efficient as touted, it
seems they need cooling to work efficiently, so that may apply to the
home as well.

--
Residing on low ground in North Staffordshire

John Williamson

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Apr 14, 2012, 6:53:24 AM4/14/12
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Moonraker wrote:
> I read recently that LEDs in cars are not as efficient as touted, it
> seems they need cooling to work efficiently, so that may apply to the
> home as well.
>
The benefits of LEDs on vehicles are the long life and resistance to
vibration. They also normally fail in a manner that leaves at least some
light being generated by the unit, which is safer than the all or
nothing when a filament lamp fails.

The efficiency savings for mobile use aren't worth bothering about
except for applications like battery powered cycle lights or torches, as
the power used by the lighting on a car is a small percentage of the
total power used to move it. At 30mph on a flat road, the absolute
maximum total lighting load on most cars, including headlamps and
foglamps, is less than 400 watts, as against ten kilowatts or more being
used to overcome rolling and air resistance.

LEDS in fixed installations are noticeably more efficient than filament
bulbs, as they use a switched mode supply, with a total comsumption of
about 10% or 15% that of the filament bulbs for the same light output.

--
Tciao for Now!

John.

Andrew Gabriel

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Apr 14, 2012, 7:30:16 AM4/14/12
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In article <9ut39a...@mid.individual.net>,
John Williamson <johnwil...@btinternet.com> writes:
> Moonraker wrote:
>> I read recently that LEDs in cars are not as efficient as touted, it
>> seems they need cooling to work efficiently, so that may apply to the
>> home as well.

Indeed it does. The lighting industry got a very bad reputation
with the dishonest claims for CFLs, and LEDs started off even worse,
e.g. quoting efficiencies with the LED chip at 25C, which is only
going to apply if you run the thing in your freezer.

> The benefits of LEDs on vehicles are the long life and resistance to
> vibration.

Also, faster 'ON' time, particularly for brake lights.

However, the lamp cluster needs to have been designed for LEDs.
Retrofitting them into a cluster designed for a filament light
source isn't going to conform to regs.

> They also normally fail in a manner that leaves at least some
> light being generated by the unit, which is safer than the all or
> nothing when a filament lamp fails.
>
> The efficiency savings for mobile use aren't worth bothering about
> except for applications like battery powered cycle lights or torches, as
> the power used by the lighting on a car is a small percentage of the
> total power used to move it. At 30mph on a flat road, the absolute
> maximum total lighting load on most cars, including headlamps and
> foglamps, is less than 400 watts, as against ten kilowatts or more being
> used to overcome rolling and air resistance.
>
> LEDS in fixed installations are noticeably more efficient than filament
> bulbs, as they use a switched mode supply, with a total comsumption of
> about 10% or 15% that of the filament bulbs for the same light output.

LEDs at that efficiency do exist, but are pricy. Most of the LEDs
you'll see at halfway affordable prices are around the same efficieny
as CFLs, and the cheaper ones are nearer the efficiency of LV halogens.

Dave Plowman (News)

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Apr 14, 2012, 7:35:13 AM4/14/12
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In article <9ut39a...@mid.individual.net>,
John Williamson <johnwil...@btinternet.com> wrote:
> LEDS in fixed installations are noticeably more efficient than filament
> bulbs, as they use a switched mode supply, with a total comsumption of
> about 10% or 15% that of the filament bulbs for the same light output.

Cars use SMPS too for LEDs.

A difference is that 12v tungsten are already more efficient than mains
ones.

I'd love to see *any* LED with the same light output as halogen mains. And
by that I mean a near 360 degree output of the same colour spectrum. Not
just measured by pointing some crude light meter at it. And using the very
worst possible tungsten as the comparison.

--
*What are the pink bits in my tyres? Cyclists & Joggers*

charles

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Apr 14, 2012, 7:48:36 AM4/14/12
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In article <jmbn48$ge3$1...@dont-email.me>,
Andrew Gabriel <and...@cucumber.demon.co.uk> wrote:
> In article <9ut39a...@mid.individual.net>,
> John Williamson <johnwil...@btinternet.com> writes:
> > Moonraker wrote:
> >> I read recently that LEDs in cars are not as efficient as touted, it
> >> seems they need cooling to work efficiently, so that may apply to the
> >> home as well.

> Indeed it does. The lighting industry got a very bad reputation
> with the dishonest claims for CFLs, and LEDs started off even worse,
> e.g. quoting efficiencies with the LED chip at 25C, which is only
> going to apply if you run the thing in your freezer.

Sorry, but while you might get 25°F in your freezer, 25°C is a slightly
warm ambient temperature.

--
From KT24

Using a RISC OS computer running v5.18

Bill Wright

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Apr 14, 2012, 8:04:25 AM4/14/12
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John Williamson wrote:

> The efficiency savings for mobile use aren't worth bothering about
> except for applications like battery powered cycle lights or torches, as
> the power used by the lighting on a car is a small percentage of the
> total power used to move it. At 30mph on a flat road, the absolute
> maximum total lighting load on most cars, including headlamps and
> foglamps, is less than 400 watts, as against ten kilowatts or more being
> used to overcome rolling and air resistance.

If that 400W could be reduced to 100W there would be worthwhile fuel
savings.

Bill

John Williamson

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Apr 14, 2012, 8:18:50 AM4/14/12
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Less than 3% at constant speed in town, less at higher speeds or when
accelerating. Stopping at one red traffic light in a five mile journey
would make more difference. Correcting the tyre pressures every time the
load changes can make more difference. Removing the toolbox or shopping
from the boot makes almost as much difference. The absolute maximum on
my car is 210W, and that's using high beam headights and rear fog lights
while I'm signalling a turn.

To get the maximum lighting load down to 100W, you'd need to replace the
headlights with ultra efficient lights, which at the moment isn't
practical. In town, using dipped beams, the load is more like 150W,
anyway. You'll only use 400W in a situation where you are driving in
foggy conditions or using four high power halogen main beam lights.

Andy Bartlett

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Apr 14, 2012, 8:38:27 AM4/14/12
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"Bill Wright" <bi...@invalid.com> wrote in message
news:jmbp4b$prs$1...@speranza.aioe.org...
Depends what you mean by worthwhile.
Back of a fag packet calcs. (assuming the vehicle does 35mpg and speed
averages 32mph) that 300W saving is 0.7% of your energy budget.
At £1.40 litre current petrol price that is about 1p per litre.
When you factor in the conversion cost I think it is a non starter.

Andy


Adam Aglionby

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Apr 14, 2012, 8:57:27 AM4/14/12
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On Apr 14, 12:48 pm, charles <char...@charleshope.demon.co.uk> wrote:
> In article <jmbn48$ge...@dont-email.me>,
>    Andrew Gabriel <and...@cucumber.demon.co.uk> wrote:
>
> > In article <9ut39aFkp...@mid.individual.net>,
> >    John Williamson <johnwilliam...@btinternet.com> writes:
> > > Moonraker wrote:
> > >> I read recently that LEDs in cars are not as efficient as touted, it
> > >> seems they need cooling to work efficiently, so that may apply to the
> > >> home as well.
> > Indeed it does. The lighting industry got a very bad reputation
> > with the dishonest claims for CFLs, and LEDs started off even worse,
> > e.g. quoting efficiencies with the LED chip at 25C, which is only
> > going to apply if you run the thing in your freezer.
>
> Sorry, but while you might get 25°F in your freezer, 25°C is a slightly
> warm ambient temperature.

Thats the Temperature Junction, Tj, in the data sheets, which is
actually a tiny area less than 1mm ^2 heating rapidly as soon as
energised.

Astounding effiency can be demonstrated by a couple of difficult to
replicate outside of the lab ,er, strategies.

Measure the output in first few miliseconds of start up with a boosted
current.

Actively chill the heatsink, to get Tj to 25C means heatsink is going
to have to start colder.

Run the device at a tiny current lowering self heating effects then
supply the numbers for massage to marketing department....

Cheers
Adam

Mike Clarke

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Apr 14, 2012, 9:41:33 AM4/14/12
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On Sat, 14 Apr 2012 13:18:50 +0100
John Williamson <johnwil...@btinternet.com> wrote:

> In town, using dipped beams, the load is more like 150W,
> anyway. You'll only use 400W in a situation where you are driving in
> foggy conditions or using four high power halogen main beam lights.

How can foggy conditions result in so much more load? A pair of front
foglamps will be the same power as a pair of dipped headlamps and the
rear foglamps will only add 21w each which will only push it up to
about 200w total

--
Mike Clarke

John Williamson

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Apr 14, 2012, 10:01:49 AM4/14/12
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You've got 200W minimum at the front, due to the dipped headlamps *and*
foglamps being on, then add the 42W drawn by the high intensity rear
lamps, plus at least 42W for brake lights and the same for indicators,
when they're being used. Plus, of course, at least 24W for side and tail
lights, not forgetting the side marker lights fitted to some cars. I was
giving maximum loads, not average ones.

Four bright halogen main beam lights are 350W just on their own.

Dave Plowman (News)

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Apr 14, 2012, 10:24:27 AM4/14/12
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In article <jmbp4b$prs$1...@speranza.aioe.org>,
It would, but that 400w includes headlights. And very few cars have LED
ones. HID are more common - and vastly more efficient than tungsten. My 35
watt units produce much more light than 55w halogen. I'm not sure how LED
compares to that.

--
*There are two kinds of pedestrians... the quick and the dead.

Dave Plowman (News)

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Apr 14, 2012, 10:26:22 AM4/14/12
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In article <9ut89g...@mid.individual.net>,
John Williamson <johnwil...@btinternet.com> wrote:
> To get the maximum lighting load down to 100W, you'd need to replace the
> headlights with ultra efficient lights, which at the moment isn't
> practical.

It already is. HID are commonly 35 watts per lamp. And produce far more
light than 55w halogen.

--
*Corduroy pillows are making headlines.

Andy Burns

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Apr 14, 2012, 10:56:54 AM4/14/12
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Dave Plowman (News) wrote:

> that 400w includes headlights. And very few cars have LED
> ones. HID are more common - and vastly more efficient than tungsten. My 35
> watt units produce much more light than 55w halogen. I'm not sure how LED
> compares to that.

The top-end Audis have optional LED headlights, it mentions 40W per unit
for the dipped beam, but doesn't state the wattage for high-beam.

Dave Plowman (News)

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Apr 14, 2012, 11:02:15 AM4/14/12
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In article <9uteak...@mid.individual.net>,
John Williamson <johnwil...@btinternet.com> wrote:
> You've got 200W minimum at the front, due to the dipped headlamps *and*
> foglamps being on,

There is absolutely no point in using both in fog. The idea of low mounted
fog lights is they cut beneath the fog and light the road. Headlights as
well will just produce scatter and blind you.

--
*We waste time, so you don't have to *

Dave Plowman (News)

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Apr 14, 2012, 11:37:53 AM4/14/12
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In article <3Y6dnT8b4_arDRTS...@brightview.co.uk>,
That's more or less the same as HID. Be interesting to do a comparison.
I'm very happy with my HID units.

The only snags with HID is the time they take to reach full brightness,
and not being a good idea to flash them, like all such types. Not a
problem in practice, but means you can't switch them on and off like
'normal' units. So you either use mirrors for dip/main beam or add
conventional mains. And some other lamps for flashing.

I suspect LED will prove cheaper, rather than better, in the scheme of
things.

--
*Indian Driver - Smoke signals only*

Andrew Gabriel

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Apr 14, 2012, 11:50:27 AM4/14/12
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In article <5280563...@davenoise.co.uk>,
"Dave Plowman (News)" <da...@davenoise.co.uk> writes:
> In article <9uteak...@mid.individual.net>,
> John Williamson <johnwil...@btinternet.com> wrote:
>> You've got 200W minimum at the front, due to the dipped headlamps *and*
>> foglamps being on,
>
> There is absolutely no point in using both in fog. The idea of low mounted
> fog lights is they cut beneath the fog and light the road.

The original "aim" was to pick out the kerb with the left one, and
the lane marking with the right one, nearer to the car than the
dip beam headlamps will effectively light. Nowadays, they're rather
more cosmetic than functional, and often can't even be adjusted to
aim/cutoff correctly.

> Headlights as well will just produce scatter and blind you.

Can do, depending on conditions, but not always.

Dave Plowman (News)

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Apr 14, 2012, 12:19:21 PM4/14/12
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In article <jmc6c3$1mu$1...@dont-email.me>,
Andrew Gabriel <and...@cucumber.demon.co.uk> wrote:
> > There is absolutely no point in using both in fog. The idea of low mounted
> > fog lights is they cut beneath the fog and light the road.

> The original "aim" was to pick out the kerb with the left one, and
> the lane marking with the right one, nearer to the car than the
> dip beam headlamps will effectively light.

All proper fog lights have a wide beam with a sharp cutoff. So can't
really be aimed as you suggest.

> Nowadays, they're rather
> more cosmetic than functional, and often can't even be adjusted to
> aim/cutoff correctly.

Some cars have extra driving lights rather than true fogs. As you say more
to differentiate the head of paper clips car from his mere salesmen.

> > Headlights as well will just produce scatter and blind you.

> Can do, depending on conditions, but not always.

Always. That's why foglights are low mounted and illegal in good
visibility. If the headlights were good in fog - why have specialised
lighting just for it?

But I'm talking about proper fog where you're reduced to walking pace.

--
*On the seventh day He brewed beer *

charles

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Apr 14, 2012, 12:21:48 PM4/14/12
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In article <20120414144...@curlew.lan>,
'cos most cars, idiotically, only allow you to use the fog lights when the
headlamps are switched on.

charles

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Apr 14, 2012, 12:23:13 PM4/14/12
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In article <528052f...@davenoise.co.uk>,
Dave Plowman (News) <da...@davenoise.co.uk> wrote:
> In article <9ut89g...@mid.individual.net>,
> John Williamson <johnwil...@btinternet.com> wrote:
> > To get the maximum lighting load down to 100W, you'd need to replace
> > the headlights with ultra efficient lights, which at the moment isn't
> > practical.

> It already is. HID are commonly 35 watts per lamp. And produce far more
> light than 55w halogen.

and even they give out a lot more light than the tungsten as supplied with
my Anglia.

Andy Burns

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Apr 14, 2012, 12:38:54 PM4/14/12
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Dave Plowman (News) wrote:

> That's more or less the same as HID. Be interesting to do a comparison.

Test drive an R8 about 5pm in winter then!

> I'm very happy with my HID units.

Ditto.

> The only snags with HID is the time they take to reach full brightness,

I think by the time they've struck and been waggled to level them,
they're at full rightness

> and not being a good idea to flash them

I don't know if that applies or not, I think mine has some normal bulbs
used for flashing and during the warm-up, you see the colour change when
these switch off, not examined them in detail though.

> like all such types. Not a
> problem in practice, but means you can't switch them on and off like
> 'normal' units. So you either use mirrors for dip/main beam or add
> conventional mains.

Dunno if mine is mirrors or some sort of shade that is raised to unmask
for high beam, again I've not looked.

Andrew Gabriel

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Apr 14, 2012, 1:38:07 PM4/14/12
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In article <5280597...@davenoise.co.uk>,
"Dave Plowman (News)" <da...@davenoise.co.uk> writes:
> In article <3Y6dnT8b4_arDRTS...@brightview.co.uk>,
> Andy Burns <usenet....@adslpipe.co.uk> wrote:
>> > that 400w includes headlights. And very few cars have LED ones. HID
>> > are more common - and vastly more efficient than tungsten. My 35 watt
>> > units produce much more light than 55w halogen. I'm not sure how LED
>> > compares to that.
>
>> The top-end Audis have optional LED headlights, it mentions 40W per unit
>> for the dipped beam, but doesn't state the wattage for high-beam.
>
> That's more or less the same as HID. Be interesting to do a comparison.
> I'm very happy with my HID units.
>
> The only snags with HID is the time they take to reach full brightness,
> and not being a good idea to flash them, like all such types. Not a
> problem in practice, but means you can't switch them on and off like
> 'normal' units. So you either use mirrors for dip/main beam or add
> conventional mains. And some other lamps for flashing.
>
> I suspect LED will prove cheaper, rather than better, in the scheme of
> things.

HIDs are cheap to make and factory fit and increase the perceived
value of the car, which makes for a good manufacturer profit margin.
Also good profit on spare parts.

LEDs are still expensive to design and manufacture for the required
performance, and don't add much (if any) perceived value over HID,
so not yet so compelling for manufacturers. It will probably come
in time though, particularly as efficiency isn't a significant
factor in this application (high efficiency jacks up LED price).

LED would perhaps allow for some clever stuff with dynamic cut-off
adjustments, such as automatic left/right side dipping based on
GPS (country, and even road-specific, e.g. where there can't be
any oncoming traffic). If the French still required yellow
headlamps, I could imagine some adjustable colour versions
too (again, derived from the GPS location).

Mike Clarke

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Apr 14, 2012, 4:02:54 PM4/14/12
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On Sat, 14 Apr 2012 17:21:48 +0100
charles <cha...@charleshope.demon.co.uk> wrote:

> 'cos most cars, idiotically, only allow you to use the fog lights
> when the headlamps are switched on.

Glad mine doesn't fall into the "most cars" category then. The scatter
from the headlights would defeat the benefit of the sharp cut-off beam
from the fog lights.

--
Mike Clarke

Dave Liquorice

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Apr 14, 2012, 4:33:48 PM4/14/12
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On Sat, 14 Apr 2012 14:41:33 +0100, Mike Clarke wrote:

> How can foggy conditions result in so much more load? A pair of front
> foglamps will be the same power as a pair of dipped headlamps and the
> rear foglamps will only add 21w each which will only push it up to
> about 200w total

Full lighting load, as standard, on my car is something over 400W.

6 x 55W (dip, main, fog), front side lights, rear lights, rear fogs.
Braking (+42W) indicating (+50W, 2 x 21W plus side marker) 500W+ ...

Admittedly if one needs the front fogs on at all then the main and
dip are off as you get too much glare back from them.

--
Cheers
Dave.



Dave Liquorice

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Apr 14, 2012, 4:46:08 PM4/14/12
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On Sat, 14 Apr 2012 17:19:21 +0100, Dave Plowman (News) wrote:

>>> Headlights as well will just produce scatter and blind you.
>>
>> Can do, depending on conditions, but not always.
>
> Always. That's why foglights are low mounted and illegal in good
> visibility. If the headlights were good in fog - why have specialised
> lighting just for it?

Quite agree.

> But I'm talking about proper fog where you're reduced to walking pace.

Proper fog that most people never ever see.

I think I've had to drop to front fogs just a handful of times up
here on the North Pennines where we almost live in the hill fog. When
the snow poles are too far apart to see from one to the next, there
is thick fog visibilty about 15' max and everything is also smoothly
covered in snow with no tracks to follow it makes for an
"interesting" drive. Fast walking pace, concentration, and "if it
gets bumpy I'm probably no longer on the road". B-)

--
Cheers
Dave.



dennis@home

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Apr 14, 2012, 4:58:55 PM4/14/12
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"Dave Plowman (News)" <da...@davenoise.co.uk> wrote in message
news:5280434...@davenoise.co.uk...
> In article <9ut39a...@mid.individual.net>,
> John Williamson <johnwil...@btinternet.com> wrote:
>> LEDS in fixed installations are noticeably more efficient than filament
>> bulbs, as they use a switched mode supply, with a total comsumption of
>> about 10% or 15% that of the filament bulbs for the same light output.
>
> Cars use SMPS too for LEDs.
>
> A difference is that 12v tungsten are already more efficient than mains
> ones.
>
> I'd love to see *any* LED with the same light output as halogen mains. And
> by that I mean a near 360 degree output of the same colour spectrum. Not
> just measured by pointing some crude light meter at it. And using the very
> worst possible tungsten as the comparison.

Let us know when you can get halogen lights that can do this
http://www.youtube.com/watch?v=znivDtjl1N4

dennis@home

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Apr 14, 2012, 5:45:44 PM4/14/12
to


"charles" <cha...@charleshope.demon.co.uk> wrote in message
news:52805d85...@charleshope.demon.co.uk...
Do you mean the rear fogs, I know of none that have front fogs where you
have to have the headlamps on as well.

gri...@gmail.com

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Apr 14, 2012, 6:10:21 PM4/14/12
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On Sat, 14 Apr 2012 21:58:55 +0100, "dennis@home"
<den...@killspam.kicks-ass.net> wrote:

>Let us know when you can get halogen lights that can do this
>http://www.youtube.com/watch?v=znivDtjl1N4

Oh, I do like that; especially the selective illumination in the face
of oncoming traffic.
Otoh, it's just another gadget/gizmo to go expensively wrong.

Dave Plowman (News)

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Apr 14, 2012, 6:27:34 PM4/14/12
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In article <jmcoef$noa$1...@news.albasani.net>,
dennis@home <den...@killspam.kicks-ass.net> wrote:
> > I'd love to see *any* LED with the same light output as halogen mains.
> > And by that I mean a near 360 degree output of the same colour
> > spectrum. Not just measured by pointing some crude light meter at it.
> > And using the very worst possible tungsten as the comparison.

> Let us know when you can get halogen lights that can do this
> http://www.youtube.com/watch?v=znivDtjl1N4

I realise you're not technical, Dennis, but multiple lamp halogens could
do exactly the same thing. Although just why you'd want to escapes me.

But it's nice to see you're impressed by computer animation.

--
*I like cats, too. Let's exchange recipes.

m...@privacy.net

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Apr 14, 2012, 7:00:01 PM4/14/12
to
On 14 Apr,
"Dave Plowman (News)" <da...@davenoise.co.uk> wrote:

> Always. That's why foglights are low mounted and illegal in good
> visibility.

Can you quote evidence of that? I'm sure that was the case in the 60s and
have trawled the net to find the rules for how high lights must be to be used
in good visibility and failed miserably in finding any evidence of the
illegality of the current spate of foglights in good visibility.

> If the headlights were good in fog - why have specialised lighting just for
> it?
>
Exactly! It's fairly rare for any fog lights to be needed. Rear foglights
should only be used when visbility is below 100 metres, so speed needs to be
restricted too. Most peeps switch on rear fog lights as soon as there's a
hint of mist, and don't slow down, being unaware that the fog lights mask
their brake lights and signals, being much brighter.

The regulations state that only one rear fog light is allowed, and that must
be on the offside, to reduce the likelyhood of them being mistaken for brake
lights.

--
B Thumbs
Change lycos to yahoo to reply

dennis@home

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Apr 14, 2012, 7:24:28 PM4/14/12
to


"Dave Plowman (News)" <da...@davenoise.co.uk> wrote in message
news:52807f0...@davenoise.co.uk...
> In article <jmcoef$noa$1...@news.albasani.net>,
> dennis@home <den...@killspam.kicks-ass.net> wrote:
>> > I'd love to see *any* LED with the same light output as halogen mains.
>> > And by that I mean a near 360 degree output of the same colour
>> > spectrum. Not just measured by pointing some crude light meter at it.
>> > And using the very worst possible tungsten as the comparison.
>
>> Let us know when you can get halogen lights that can do this
>> http://www.youtube.com/watch?v=znivDtjl1N4
>
> I realise you're not technical, Dennis, but multiple lamp halogens could
> do exactly the same thing. Although just why you'd want to escapes me.

I realise you don't know as much as you think but the optics to do that with
halogen lamps would be rather difficult.
The filament would have to be too long to actually make the sharp cut off
required.
But I guess you don't know much about the differences between LED lamps and
filament lamps.

>
> But it's nice to see you're impressed by computer animation.

Its not all animation, but I realise that you can't tell the difference.
Even Mickey mouse cartoons are more impressive than you these days.

PeterC

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Apr 15, 2012, 4:20:27 AM4/15/12
to
On Sat, 14 Apr 2012 21:46:08 +0100 (BST), Dave Liquorice wrote:

>> But I'm talking about proper fog where you're reduced to walking pace.
>
> Proper fog that most people never ever see.
>
> I think I've had to drop to front fogs just a handful of times up
> here on the North Pennines where we almost live in the hill fog. When
> the snow poles are too far apart to see from one to the next, there
> is thick fog visibilty about 15' max and everything is also smoothly
> covered in snow with no tracks to follow it makes for an
> "interesting" drive. Fast walking pace, concentration, and "if it
> gets bumpy I'm probably no longer on the road". B-)

Last had that coming home from walking on Kinder Scout. Brilliant day on the
tops but cloud below 1500'.
On the last roundabout on the southern edge of Derby I lost the kerb and had
to go round again; I could just see the signs fron about 5 yards away.

A bit further on we turned L into a pub's car-park (we often used that pub)
and were followed by another car. The other car realised that we'd parked
and swung L. It got to an exit (visibility there was about 10 yards), turned
L onto a minor road, reached the A-road from which it had come and turned R!
It had Channel Island plates, so it might just have been a tad lost - only
180 deg. though.
--
Peter.
The gods will stay away
whilst religions hold sway

charles

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Apr 15, 2012, 4:28:12 AM4/15/12
to
In article <20120414210...@curlew.lan>,
agreed

Dave Plowman (News)

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Apr 15, 2012, 4:47:03 AM4/15/12
to
In article <52808147CB%brian...@lycos.co.uk>,
<m...@privacy.net> wrote:
> On 14 Apr,
> "Dave Plowman (News)" <da...@davenoise.co.uk> wrote:

> > Always. That's why foglights are low mounted and illegal in good
> > visibility.

> Can you quote evidence of that? I'm sure that was the case in the 60s
> and have trawled the net to find the rules for how high lights must be
> to be used in good visibility and failed miserably in finding any
> evidence of the illegality of the current spate of foglights in good
> visibility.

You can't have tried very hard. It's in the highway code.

http://www.direct.gov.uk/en/TravelAndTransport/Highwaycode/DG_069859

although that seems to suggest they must be used with headlights. Which
completely defeats the purpose of them.

> > If the headlights were good in fog - why have specialised lighting
> > just for it?
> >
> Exactly! It's fairly rare for any fog lights to be needed. Rear
> foglights should only be used when visbility is below 100 metres, so
> speed needs to be restricted too. Most peeps switch on rear fog lights
> as soon as there's a hint of mist, and don't slow down, being unaware
> that the fog lights mask their brake lights and signals, being much
> brighter.

They are normally the same brightness as stop lamps or indictors. They are
also very useful in heavy rain in daylight. They allow you to see there is
a car in front before you can actually see the car itself.

> The regulations state that only one rear fog light is allowed, and that
> must be on the offside, to reduce the likelyhood of them being mistaken
> for brake lights.

Both my cars have twin rear fog lights.

--
*What do little birdies see when they get knocked unconscious? *

Dave Plowman (News)

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Apr 15, 2012, 4:53:21 AM4/15/12
to
In article <jmd0vc$7lp$1...@news.albasani.net>,
dennis@home <den...@killspam.kicks-ass.net> wrote:
> > I realise you're not technical, Dennis, but multiple lamp halogens
> > could do exactly the same thing. Although just why you'd want to
> > escapes me.

> I realise you don't know as much as you think but the optics to do that
> with halogen lamps would be rather difficult. The filament would have
> to be too long to actually make the sharp cut off required.

A sharp cutoff is achieved with a french flag. Many many cars with halogen
and HID units do this. LEDs will be no different. It's down to the optics,
not light source.

> But I guess you don't know much about the differences between LED lamps
> and filament lamps.

Obviously a lot more than you.

> > But it's nice to see you're impressed by computer animation.

> Its not all animation, but I realise that you can't tell the difference.
> Even Mickey mouse cartoons are more impressive than you these days.

If they have to resort to animation, it means real world conditions don't
show the effects they're conning the likes of you into believing. Are you
actually dribble? He's another who believes everything he sees in adverts.

--
*Why doesn't Tarzan have a beard? *
Message has been deleted

Rod Speed

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Apr 15, 2012, 5:38:59 AM4/15/12
to
Dave Plowman (News) <da...@davenoise.co.uk> wrote
> <m...@privacy.net> wrote
>> Dave Plowman (News) <da...@davenoise.co.uk> wrote

>>> Always. That's why foglights are low mounted and illegal in good
>>> visibility.

>> Can you quote evidence of that? I'm sure that was the case in the 60s
>> and have trawled the net to find the rules for how high lights must be
>> to be used in good visibility and failed miserably in finding any
>> evidence
>> of the illegality of the current spate of foglights in good visibility.

> You can't have tried very hard. It's in the highway code.
> http://www.direct.gov.uk/en/TravelAndTransport/Highwaycode/DG_069859

> although that seems to suggest they must be used with headlights.

No it does not.

> Which completely defeats the purpose of them.

Which is presumably why it doesn't say that.

ARWadsworth

unread,
Apr 15, 2012, 5:40:49 AM4/15/12
to
Dave Liquorice wrote:

> Fast walking pace, concentration, and "if it
> gets bumpy I'm probably no longer on the road". B-)

vbg


--
Adam


Dave Liquorice

unread,
Apr 15, 2012, 7:09:54 AM4/15/12
to
On Sun, 15 Apr 2012 00:00:01 +0100, m...@privacy.net wrote:

> Rear foglights should only be used when visbility is below 100 metres,

Correct.

> so speed needs to be restricted too. Most peeps switch on rear fog
> lights as soon as there's a hint of mist,

Only stupid prats but there does seem to be a lot of them about. If
it's having them on when visibilty is >100m it's leaving them on in
traffic.

> The regulations state that only one rear fog light is allowed,

Rubbish many cars have two rear fog lights. It's only the smaller
cheaper cars that have one and the coresponding place in the other
light cluster has the reversing light.

> and that must be on the offside,

True if there is only one.

--
Cheers
Dave.



ARWadsworth

unread,
Apr 15, 2012, 7:25:37 AM4/15/12
to
When I had a Berlingo (only one rear fog light on the OS) I got a MOT
failure for a NS rear fog light not working and a Ł5 bill to fit a new bulb.
Bet you can guess what I did with that bill:-)

The mutual agreement reached between myself and the owner of the garage
after the argument was that it would be best if I did not use their garage
again.

--
Adam


Dave Liquorice

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Apr 15, 2012, 7:16:25 AM4/15/12
to
On 15 Apr 2012 09:07:56 GMT, Huge wrote:

> My Disco 3 has a mechanical interlock in the switch which means you
> cannot switch the fogs on without having the headlamps on, and the front
> fogs come on before the rear ones. Both of which I find bizarre and
> irritating.

Also means that the rear fogs get turned off automatically when you
turn off the main lights. Years ago I suspect the main reason for
rear fogs being on when they shouldn't have been was due to lack of
interlock/self cancelling and tiny tell tale out of the drivers
normal view.

Surprised a DIII has a mechanical interlock, both DII's I've had they
have been under control of the BCU. Are the front "fogs" real fogs or
"auxillary driving lights"? A real fog has low wide beam with the cut
off on the ground at around 30' or less from the front of the
vehicle. No good for night driving on their own.

--
Cheers
Dave.



Message has been deleted

Dave Plowman (News)

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Apr 15, 2012, 7:34:35 AM4/15/12
to
In article <9uvj9m...@mid.individual.net>,
Rod Speed <rod.sp...@gmail.com> wrote:
> > http://www.direct.gov.uk/en/TravelAndTransport/Highwaycode/DG_069859

> > although that seems to suggest they must be used with headlights.

> No it does not.

I wouldn't expect you to understand English. Thanks for confirming it.
It must have been the likes of you who wrote that HC rule.

--
*Middle age is when it takes longer to rest than to get tired.

Mike Clarke

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Apr 15, 2012, 9:38:33 AM4/15/12
to
On Sun, 15 Apr 2012 00:00:01 +0100
<m...@privacy.net> wrote:

> The regulations state that only one rear fog light is allowed,and
> that must be on the offside, to reduce the likelyhood of them being
> mistaken for brake lights.

http://www.legislation.gov.uk/uksi/1989/1796/schedule/11/made states
that it's mandatory to have (at least) one rear fog lamp but 2 lamps are
optional. In the event of only one lamp then it must be on the
centre-line or offside of the vehicle but there are no restrictions if
2 lamps are fitted.

--
Mike Clarke

Andy Burns

unread,
Apr 15, 2012, 9:48:55 AM4/15/12
to
Mike Clarke wrote:

> <m...@privacy.net> wrote:
>
>> The regulations state that only one rear fog light is allowed,and
>> that must be on the offside
>
> http://www.legislation.gov.uk/uksi/1989/1796/schedule/11/made
>
> states that it's mandatory to have (at least) one rear fog lamp but 2
> lamps are optional. In the event of only one lamp then it must be on
> the centre-line or offside of the vehicle but there are no
> restrictions if 2 lamps are fitted.

So you could be stupid and have two on the nearside, so close together
that they're barely distinguishable, it only mentions separation between
stop and fog lamps ...

dennis@home

unread,
Apr 15, 2012, 12:27:15 PM4/15/12
to


"Dave Plowman (News)" <da...@davenoise.co.uk> wrote in message
news:5280b84...@davenoise.co.uk...
> In article <jmd0vc$7lp$1...@news.albasani.net>,
> dennis@home <den...@killspam.kicks-ass.net> wrote:
>> > I realise you're not technical, Dennis, but multiple lamp halogens
>> > could do exactly the same thing. Although just why you'd want to
>> > escapes me.
>
>> I realise you don't know as much as you think but the optics to do that
>> with halogen lamps would be rather difficult. The filament would have
>> to be too long to actually make the sharp cut off required.
>
> A sharp cutoff is achieved with a french flag. Many many cars with halogen
> and HID units do this. LEDs will be no different. It's down to the optics,
> not light source.
>

What makes you think LEDs need a baffle to throw half the light away?


>> But I guess you don't know much about the differences between LED lamps
>> and filament lamps.
>
> Obviously a lot more than you.

Obviously not.

>
>> > But it's nice to see you're impressed by computer animation.
>
>> Its not all animation, but I realise that you can't tell the difference.
>> Even Mickey mouse cartoons are more impressive than you these days.
>
> If they have to resort to animation, it means real world conditions don't
> show the effects they're conning the likes of you into believing. Are you
> actually dribble? He's another who believes everything he sees in adverts.

I wonder how many things started out by someone showing a drawing, or a
slide show to someone else before it became something real..
lets think a few seconds..
that would be almost everything in the last decade or three.

Mike Barnes

unread,
Apr 15, 2012, 5:50:52 AM4/15/12
to
PeterC <giraffe...@homecall.co.uk>:
>On Sat, 14 Apr 2012 21:46:08 +0100 (BST), Dave Liquorice wrote:
>
>>> But I'm talking about proper fog where you're reduced to walking pace.
>>
>> Proper fog that most people never ever see.
>>
>> I think I've had to drop to front fogs just a handful of times up
>> here on the North Pennines where we almost live in the hill fog. When
>> the snow poles are too far apart to see from one to the next, there
>> is thick fog visibilty about 15' max and everything is also smoothly
>> covered in snow with no tracks to follow it makes for an
>> "interesting" drive. Fast walking pace, concentration, and "if it
>> gets bumpy I'm probably no longer on the road". B-)
>
>Last had that coming home from walking on Kinder Scout. Brilliant day on the
>tops but cloud below 1500'.
>On the last roundabout on the southern edge of Derby I lost the kerb and had
>to go round again; I could just see the signs fron about 5 yards away.

You can see why it makes sense to fit proper front fog lights to cars
even though they're only needed once in a blue moon. When you need them,
you really need them. It's a pity about those prats that switch them on
at the first hint of mist, and take their time turning them off again.

--
Mike Barnes

Dave Plowman (News)

unread,
Apr 15, 2012, 1:59:10 PM4/15/12
to
In article <jmest3$lds$1...@news.albasani.net>,
dennis@home <den...@killspam.kicks-ass.net> wrote:
> > A sharp cutoff is achieved with a french flag. Many many cars with
> > halogen and HID units do this. LEDs will be no different. It's down to
> > the optics, not light source.
> >

> What makes you think LEDs need a baffle to throw half the light away?

What makes you think there's another way of doing it? Not a knowledge of
optics, obviously.

--
*Marriage changes passion - suddenly you're in bed with a relative*

dennis@home

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Apr 15, 2012, 2:33:04 PM4/15/12
to


"Dave Plowman (News)" <da...@davenoise.co.uk> wrote in message
news:5280ea4...@davenoise.co.uk...
> In article <jmest3$lds$1...@news.albasani.net>,
> dennis@home <den...@killspam.kicks-ass.net> wrote:
>> > A sharp cutoff is achieved with a french flag. Many many cars with
>> > halogen and HID units do this. LEDs will be no different. It's down to
>> > the optics, not light source.
>> >
>
>> What makes you think LEDs need a baffle to throw half the light away?
>
> What makes you think there's another way of doing it? Not a knowledge of
> optics, obviously.

So do you know the difference between a filament and a silicon junction?

Adam Aglionby

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Apr 15, 2012, 3:10:59 PM4/15/12
to
On Apr 14, 9:58 pm, "dennis@home" <den...@killspam.kicks-ass.net>
wrote:
> "Dave Plowman (News)" <d...@davenoise.co.uk> wrote in messagenews:5280434...@davenoise.co.uk...
>
> > In article <9ut39aFkp...@mid.individual.net>,
> >   John Williamson <johnwilliam...@btinternet.com> wrote:
> >> LEDS in fixed installations are noticeably more efficient than filament
> >> bulbs, as they use a switched mode supply, with a total comsumption of
> >> about 10% or 15% that of the filament bulbs for the same light output.
>
> > Cars use SMPS too for LEDs.
>
> > A difference is that 12v tungsten are already more efficient than mains
> > ones.
>
> > I'd love to see *any* LED with the same light output as halogen mains. And
> > by that I mean a near 360 degree output of the same colour spectrum. Not
> > just measured by pointing some crude light meter at it. And using the very
> > worst possible tungsten as the comparison.
>
> Let us know when you can get halogen lights that can do thishttp://www.youtube.com/watch?v=znivDtjl1N4

Citreon DS famously had steering headlights, think there has been a
few since, self levelling are very common via tilt servo.

Advantage here is probabkly very efficient optics getting most of
light from LED in collimated beam and then using multiple beams to
cover the area.

Works well in a car becasue area needing lit is relatively narrow.

Cheers
Adam

Rod Speed

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Apr 15, 2012, 4:05:58 PM4/15/12
to
Dave Plowman (News) <da...@davenoise.co.uk> wrote
> Rod Speed <rod.sp...@gmail.com> wrote
>> Dave Plowman (News) <da...@davenoise.co.uk> wrote

>>> http://www.direct.gov.uk/en/TravelAndTransport/Highwaycode/DG_069859

>>> although that seems to suggest they must be used with headlights.

>> No it does not.

> I wouldn't expect you to understand English. Thanks for confirming it.
> It must have been the likes of you who wrote that HC rule.

You never could bullshit your way out of a wet paper bag.

David

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Apr 15, 2012, 5:01:58 PM4/15/12
to
On 15/04/2012 18:59, Dave Plowman (News) wrote:
> In article<jmest3$lds$1...@news.albasani.net>,
> dennis@home<den...@killspam.kicks-ass.net> wrote:
>>> A sharp cutoff is achieved with a french flag. Many many cars with
>>> halogen and HID units do this. LEDs will be no different. It's down to
>>> the optics, not light source.
>>>
>
>> What makes you think LEDs need a baffle to throw half the light away?
>
> What makes you think there's another way of doing it? Not a knowledge of
> optics, obviously.
>

Seriously?

you do realise that you just modulate the drive current to turn a LED
on/off.

No mechanical parts required.

cheers

David

Message has been deleted

Andrew Gabriel

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Apr 15, 2012, 5:19:58 PM4/15/12
to
In article <9v0rl0...@mid.individual.net>,
Huge <Hu...@nowhere.much.invalid> writes:
> And that directs the light in a particular direction how, exactly?

An LED-based headlamp is likely to be multi-LED source.
With LEDs being tiny sources anyway, it's relatively easy to
build optics around them to very accurately direct each LED
source to a specific part of the output beam. This means you
can do beam dipping simply by switching off those LEDs which
give the high beam. As I eluded in another post, you could
have beams which are much more dynamically adjustable than
just main/dip. Could also vary intensity of parts of the beam,
and unlike either filament or HID, colour shift would be
minimal if you did this.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

David

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Apr 15, 2012, 5:30:30 PM4/15/12
to
On 15/04/2012 22:07, Huge wrote:
> On 2012-04-15, David<nos...@nospam.com> wrote:
> And that directs the light in a particular direction how, exactly?
>
>

by having multiple LEDs that you simple switch on/off

this is not a smooth transition but rather a discrete group of settings
- a digital rather than analogue directional control if you like.

Dave Plowman (News)

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Apr 15, 2012, 6:47:14 PM4/15/12
to
In article <jmf48v$65q$1...@news.albasani.net>,
dennis@home <den...@killspam.kicks-ass.net> wrote:
> > What makes you think there's another way of doing it? Not a knowledge
> > of optics, obviously.

> So do you know the difference between a filament and a silicon junction?

LEDs don't need optics, then?

--
*The average person falls asleep in seven minutes *

Dave Plowman (News)

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Apr 15, 2012, 6:48:42 PM4/15/12
to
In article <84GdnYLEGfKhqhbS...@eclipse.net.uk>,
Which discussion do you think you're reading?

--
*Can atheists get insurance for acts of God? *

Dave Plowman (News)

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Apr 15, 2012, 6:51:44 PM4/15/12
to
In article <jmfe1u$k1c$1...@dont-email.me>,
Andrew Gabriel <and...@cucumber.demon.co.uk> wrote:
> An LED-based headlamp is likely to be multi-LED source.
> With LEDs being tiny sources anyway, it's relatively easy to
> build optics around them to very accurately direct each LED
> source to a specific part of the output beam.

High power LEDs are tiny sources? Some data, please.

However, to provide a sharp cutoff, you'll still need some form of flag.
Just like any other light source.

--
*When it rains, why don't sheep shrink? *

dennis@home

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Apr 16, 2012, 5:47:15 AM4/16/12
to


"Dave Plowman (News)" <da...@davenoise.co.uk> wrote in message
news:528104a...@davenoise.co.uk...
> In article <jmf48v$65q$1...@news.albasani.net>,
> dennis@home <den...@killspam.kicks-ass.net> wrote:
>> > What makes you think there's another way of doing it? Not a knowledge
>> > of optics, obviously.
>
>> So do you know the difference between a filament and a silicon junction?
>
> LEDs don't need optics, then?

Stop wriggling.

Dave Plowman (News)

unread,
Apr 16, 2012, 8:06:32 AM4/16/12
to
In article <jmgpr2$33q$1...@news.albasani.net>,
Ok Dennis. Explain how you get a sharp cutoff on an LED without using
optics. My breath is bated.

Hint: Just how the light is produced - filament or discharge etc make
little difference. The more of a point source it is just makes the optics
easier.

--
*There are two sides to every divorce: Yours and shit head's*

Steve Firth

unread,
Apr 16, 2012, 9:15:50 AM4/16/12
to
"Dave Plowman (News)" <da...@davenoise.co.uk> wrote:
> In article <jmgpr2$33q$1...@news.albasani.net>,
> dennis@home <den...@killspam.kicks-ass.net> wrote:
>
>
>> "Dave Plowman (News)" <da...@davenoise.co.uk> wrote in message
>> news:528104a...@davenoise.co.uk...
>>> In article <jmf48v$65q$1...@news.albasani.net>,
>>> dennis@home <den...@killspam.kicks-ass.net> wrote:
>>>>> What makes you think there's another way of doing it? Not a
>>>>> knowledge of optics, obviously.
>>>
>>>> So do you know the difference between a filament and a silicon
>>>> junction?
>>>
>>> LEDs don't need optics, then?
>
>> Stop wriggling.
>
> Ok Dennis. Explain how you get a sharp cutoff on an LED without using
> optics. My breath is bated.
>
> Hint: Just how the light is produced - filament or discharge etc make
> little difference. The more of a point source it is just makes the optics
> easier.


Dennis seems to be hitting new depths. Power LEDs generally have one or two
reflectors (sometimes the manufacturer has a reflector in the LED ) and
usually two lenses, one incorporated in the package and a second lens and
reflector for the array. Blathering away than a lens is not required is,
errm total bollocks, again.

Dave Plowman (News)

unread,
Apr 16, 2012, 9:30:30 AM4/16/12