Just searching for H11 LED canbus Fog Light bulbs and some have resistors attached and some do not... can anybody teach me more and tell me if we need them?

Mines an 2007...

I've done everything else, now doing Fog and Cornering bulbs.

These are great for the cornering lamps:http://www.hids4u.co.uk/h8-28-led-foglight...power.html No resistors required.

I would advise you not to put LEDs in your fog lamps - you would render them useless as the beam is ruined, causing light to stray upwards and refract of the fog. The higher colour temperature is also not helpful, particularly for poor weather conditions. The same effect happens to the cornering lamps, however, I find it is beneficial in that case, as long as good bulbs (i.e. the above) are used to maintain the intensity in the original beam area.  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver

Thanks for the link... To be honest I very rarely put my fog lights on unless it is actual thick fog outside! So LED fog light bulbs are really a waste of money for me, it's just my OCD was kicking in and wanting them all matching

Unless you go for fog lights actually designed as/for LEDs

http://www.ebay.co.uk/itm/like/33167542819...mp;ff13=80

Click image to enlarge

Actually no, Mike. LEDs can't produce a good fog beam at all (though obviously, those are still a scale better than a retro-fit). They are very popular, of course, but they will cause too much glare to work like a fog lamp should. Good for show though, which is why the majority want them anyway.  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver

Neither can a halogen bulb. It's all down to the design of the reflector

If the lens and reflector is designed for the LED then there's no reason it should give more glare than a traditional lamp. Getting a good tight beam cut off is the key. Also having the lamp as low as possible is beneficial too. The best fog lights I've used were on my 309GTI. They were right at the bottom of the front valance and cut below fog to give good light up the road. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

It's down to to the fact that a halogen or HID lamp has a small filament/arc from which the light is produced. Reflectors and lenses are important, but the small focal point is needed to begin with. The larger area of the LED from which the light is produced means it's not good for a fog beam, and can't produce a spot beam at all.  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver

I agree that LEDs are no good as a swap for halogen bulbs for the reason you state. If starting from scratch one could design the reflector and lens to deal with the non-point source. It's more involved, of course, but it is possible. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

A "passable" fog beam can be created, by facing the LEDs towards the reflectors (so, really, bigger reflectors are needed too), but it's still not as precise as it should be (then when it comes to spot beams, even that isn't enough).  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver

You do realise that manufacturers are making LED fog lights, don't you? They're on the market and they have cut off beams etc. in exactly the same way that halogen fog lights do. They are also making LED headlights, indeed Audi have LED headlights on some of their range now.

The laws of optics have been known for hundreds of years, are well understood and relatively simple too - school boy physics really. If one knows the source of the light, and it can be a point source, a linear source or a 2/3D source, one can determine the paths of the light and then design reflectors and lenses to direct that light where one wishes.

The main point is that you can't just change a halogen bulb for an LED bulb in a given light unit and expect it to perform correctly. This is because the light won't be hitting the reflectors and lenses in the correct manner for the beam to be correctly formed.

Oh, and don't forget that an incandescent bulb isn't actually a point source, it's a line source - the filament has a much larger dimension one way than the other. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

I'll post a pic of my fogs this evening

Nice, direct, and defined

Yes, I do realise they make them - they do so because nowadays fog lights are used more to look "cool" than in genuine fog, and people don't realise/aren't interested in the differences in beam quality. As I say, the reflector facing ones are acceptable, if not perfect, but others aren't good. I did say that this was on a different level to the effect of a retro-fit (I am being picky). Standard headlight beams are a much less-specific beam so are fine.

Lenses and reflectors can only apply changes to all light rays any given point; if it hits at different angles from the start, both rays are reflected/refracted in the same manner, and so must remain heading in different directions.

Aside from the beam issue, the 6000k colour temperature at which LEDs produce most light, and spikey spectrum does very little favours in bad weather (or indeed in general).  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver

DRL

Click image to enlarge

Click image to enlarge

Thanks for going to the effort, Mike.

I never doubted that those particular lights would produce a reasonable beam, but I think my initial comments came across a bit strongly which was not as intended (too often the way with online discussion).

I still maintain that LEDs will always be very subtly worse than halogen, and it's very hard to see unless in actual fog, but as above, I'm only being very picky here. The colour is still the other issue though.  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver