HID's do they lose their effectiveness?

[T9 man]

Can't help wondering if my eye sight is slowly failing me! :sad2: Have factory fitted HID's on my car, and they just don't seem to be as bright on the road as when I first got the car over 7 years ago! When I first had the car, compared to the halogen lights on my old Saab these HID's had a wow factor on the level of light they produced :amazed:

I know it is not an electrical problem i.e. earthing or any other electrical contact issues!

So is it me or has anyone else noticed a similar phenomenon with their own HID's?

 

[HDi fun]

HIDs fail in one hit, they don't dim gradually.

The level of light is an interesting one. When I first tried HIDs I was impressed, as everyone is. They are arguably and measurably brighter than Halogen or even todays Xenon filled high brightness upgrade lamps.

But - I started to wonder whether I actually see any better with them. Visual acuity and perception are quite subjective and vary widely from person to person. Gas discharge lamps do not provide a continuous colour spectrum, instead the spectrum is comprised of a number of discrete bands. In the case of HIDs these bands create the effect of white light, or daylight.

But daylight, is a continuous spectrum and we can assume this to be natural for our eyes. Incandescent lights (filament lights) also produce a continuous spectrum. But it's much stronger in the longer wavelengths (yellows and reds) than it is in the shorter wavelengths.

What I driving at is that a decent filament lamp might well provide better visual acuity (due to the nature of the light it provides) than an HID (which provides only an approximation of white light) despite being yellower in appearance and less bright.

Any thoughts?

 

[T9 man]

Without doubt the light discharge with that all too familiar blue tinge, certainly projects the light further on the road/motorway.
But I was just thinking to myself last night on the way back home from friends on a familiar road, that I seem to be experiencing a slight dullness from the lamps! I was driving alongside an old M reg golf which clearly had the HID conversion done to it, this car produced a beam of light when we drew level which was a good 5 metres ahead of my mine and it was not on full beam! It was then that I started to question the effectiveness!

So before I think about spending lots of money replacing the lamps and starters, because once that I perceive there to be a fault with the car, I will not stop until the problem is rectified; however much it costs! I thought I would seek guidance and wisdom from those who may know the answer to my query!

 

[HDi fun]

The aftermarket conversions are illegal. So the Golf might well project a longer, if ill defined beam.

Also, if your car is 7 years old it's possible that you need to get the insides of the headlights cleaned - reflectors and lenses. This might fix the problem.

 

[turbonutter69]

The aftermarket conversions are illegal. So the Golf might well project a longer, if ill defined beam.

Also, if your car is 7 years old it's possible that you need to get the insides of the headlights cleaned - reflectors and lenses. This might fix the problem.

They are only illegal if they've been cowboy fitted.
If you get everything you need Ie Auto leveler etc then they will be perfectly legal.

 

[lutonmatt]

will say its most likey down to the headless being dirty even if they look clean they will tarnish a bit

mine are no were near as good as when i fitted them
but both my headlights are full of mud does not help

 

[HDi fun]

They are only illegal if they've been cowboy fitted.
If you get everything you need Ie Auto leveler etc then they will be perfectly legal.

No they won't.

The only way to retrofit them legally is to fit headlight enclosures from another model in the range which had HiDs as a factory option. The reflector geometry of a HID enclosure is totally different to an enclosure for a filament lamp.

You will still need the auto levelling and washing systems besides.

 

[turbonutter69]

No they won't.

The only way to retrofit them legally is to fit headlight enclosures from another model in the range which had HiDs as a factory option. The reflector geometry of a HID enclosure is totally different to an enclosure for a filament lamp.

You will still need the auto levelling and washing systems besides.

I know this. But there are aftermarket products that can be bought and used.

 

[HDi fun]

I know this. But there are aftermarket products that can be bought and used.

There are indeed. And they can be used. But they are not road legal unless the enclosures are designed to take HID lamps.

In a filament lamp the light source, the filament is mounted horizontally. The light source in a HID lamp is an electric arc and the light source is vertical. The reflector geometry is completely different. And the filament enclosures are only E-marked and compliant when E marked filament lamps are fitted.

The HID ones may well be E marked by the type approval is only valid in the correc enclosure.

And, as you say, you MUST have, additionally, a washing system and automatic beam levelling (or automatic suspension levelling).

Check here:- http://www.dft.gov.uk/pgr/roadsafety/drs/hidheadlamps

 

[turbonutter69]

Yes buddy I know about the laws pal. I must have miss understood. Because I was talking about a complete unit being bought.

 

[HDi fun]

Yes buddy I know about the laws pal. I must have miss understood. Because I was talking about a complete unit being bought.

Totally different, I agree (as you and I normally do ). If you get a whole setup from a similar model which has factory HIDS then yes, that's fine. You might have to declare it as a mod but it's not going to attract any attention so no-one's likely to be any the wiser.

 

[T9 man]

The aftermarket conversions are illegal. So the Golf might well project a longer, if ill defined beam.

Also, if your car is 7 years old it's possible that you need to get the insides of the headlights cleaned - reflectors and lenses. This might fix the problem.

This is true, and I must confess! that this scenario had not entered my head :amuse:
The Beast had everything installed in the first instance; auto levelling, pop up headlight washers, so will call the main dealer tomorrow and get them to check the lenses or change the lamps altogether! huge thanks for the heads up HDi

 

[T9 man]

I know this. But there are aftermarket products that can be bought and used.

I gather some of these kits are quite high performing? Seven years is a long long time in technology, so the light performance that I saw on the Golf might be a sign of things to come as it were!
Time will tell! cheers for the info TN69

 

[Eclaire]

I know that there are (at least here in Japan) different HID power levels too. I forget what they are exactly, but for instance, 80's 90's and 100's. The higher the number meaning a higher intensity. So if you had 80's and the other guy had 100's, his would definitely be brighter as well. As you said, you might just have older ones that aren't as strong as some of the newer ones.

 

[HDi fun]

I think that restricting lamp brightness by input watts is silly now. Filament lamps in the UK must not exceed 55w (maybe 60w). But it's OK for Osram and Philips, amongst others, to produce double brightness lamps.

That's like trying to restrict the top speed of a car by making the filler neck of the fuel tank narrower.