Headlight LED -- F2 vs F3 vs NB35

Dumb question, sorry...
Looking on Amazon for LED bulbs is very confusing, a plethora of choices and brands.
Sometimes just few words about the chips and barely enough information beside the type of connectors.
Is there any way to identify visually or by standard F2, F3, N35 (H4 9003) led bulbs?
Thanks!
Click to expand...
I have had, and continue to have, the same question. I bothered you not so long ago about this because I was not sure what H7 bulb I should order because I couldn't tell if it was an F2/3 or not by the description. You very kindly responded and pointed me in the right direction, but it seems rather unfair for everyone to keep doing that to you.

So, other than perpetually pestering you about what we should be buying, I am never certain if what I am looking at is a G6, F2, F3, etc., bulb because I never see that terminology listed anywhere in the description.
I still don't know what those monikers even mean.
 
Sidekick said:
Dumb question, sorry...
Looking on Amazon for LED bulbs is very confusing, a plethora of choices and brands.
Sometimes just few words about the chips and barely enough information beside the type of connectors.
Is there any way to identify visually or by standard F2, F3, N35 (H4 9003) led bulbs?
Thanks!
Click to expand...

Most of us just buy one of the ones listed. Check the links here and compare the photo visually to the models listed as there are sometimes multiple vendors selling the same bulb under different packaging. Thee is a thread here somewhere with what to look for in a bulb. I agree there's a lot of bad style styles out there and it's confusing!

If you're not sure, pop the link / photo in here for us to look at and give a yay or nay to.
 
A year later.....

18k miles, over 450 hours, hot Summer temps, about 1/3 night driving and no one ever flashed me.

So what might be considered wrong with the F3, a larger led die, makes it better.
I really like how the F3 really lights up the sides of the road and I can also see better down the road.
The F3 with its slightly larger emitter spreads out the hot spot just enough to put light where the halogen bulb is lacking.
The halogen bulb creates too much of a laser beam effect and does not illuminate the sides of the road very well.

Correct focus is what now makes the newer LEDs work in a Halogen reflector.
Now focus is a very important attribute that the Halogen bulb has over the LED or the HID.
The need for the LED to have the exact focus of the Halogen filament is a bit over blown.
The filament diameters are: Halogen 1.4 mm, LED 2.3 mm, HID 5 mm.
But the HID and LED have 4 times the raw Lumens of the Halogen bulb.
Doubling the the raw lumens on a Halogen bulb is not enough, besides it shortens its already short life.
The LED, with a better focus than the HID, can project better than the HID.

The handicap for us is the H4 system in the ST.
The ST reflector does a good job of spreading out the light.
The H4 low beam is not at the focus point so you do not get the throw that a dual headlight system will do anyway.
This is the tradeoff that is made in the H4 system to create the sharp cutoff that the H4 is famous for.
The difference of the halogen bulb being omnidirectional and the LED projects side to side is not a problem.
The LED is more efficient in a rectangular headlight and after all the beam pattern is horizontal anyway.
The arguments that a LED bulb will not work in a halogen reflector are no longer valid.

The bottom line is, on a dark country road, I can see more than the necessary 100 yards down the road on low beam with either the F2 or F3 design without glaring opposing traffic.

For the record.
The F2 and the F3 could improve focus with a little more wafer thinning.
The process that removes the excess backing and enables the chip manufactures to squeeze their chips into thinner packages.
This would impact yield but would also improve thermal performance and sharper focus.
This may not be necessary as the current crop of LED bulbs have sufficient focus to be equivalent to Halogen bulb.

I also put the F3 into other vehicles that have DOT reflector headlights that have a stronger hotspot.
These headlights also work very well with the F3 bulb and project further than the ST H4.
Just make sure that you carefully adjust the beam pattern with any upgrade.
If your headlights are old they should be cleaned and polished.
If they are really old you might be surprised that an OEM replacement headlight housing will make a huge improvement.

Opinion: the nb35 "six pack" LED would be good for high beam, the F2 "thin LED" would be good for the low beam and the F3 "in between" LED would be a good compromise. Here I am splitting hairs so take it for what it is worth.

The recent Cougar motors "flagship" bulb is an interesting cross over. It runs at the F2 power level and housing with the bigger F3 chip.

Projector headlights loose half the available light compared to a reflector headlight.
So you will want the highest power and most lumen LED for a projector headlight because of its reduced light output.

I added an update to the first post for new readers.
 
spiderman302 said:
A year later.....

18k miles, over 450 hours, hot Summer temps, about 1/3 night driving and no one ever flashed me.

So what might be considered wrong with the F3, a larger led die, makes it better.
I really like how the F3 really lights up the sides of the road and I can also see better down the road.
The F3 with its slightly larger emitter spreads out the hot spot just enough to put light where the halogen bulb is lacking.
The halogen bulb creates too much of a laser beam effect and does not illuminate the sides of the road very well.

Correct focus is what now makes the newer LEDs work in a Halogen reflector.
Now focus is a very important attribute that the Halogen bulb has over the LED or the HID.
The need for the LED to have the exact focus of the Halogen filament is a bit over blown.
The filament diameters are: Halogen 1.4 mm, LED 2.3 mm, HID 5 mm.
But the HID and LED have 4 times the raw Lumens of the Halogen bulb.
Doubling the the raw lumens on a Halogen bulb is not enough, besides it shortens its already short life.
The LED, with a better focus than the HID, can project better than the HID.

The handicap for us is the H4 system in the ST.
The ST reflector does a good job of spreading out the light.
The H4 low beam is not at the focus point so you do not get the throw that a dual headlight system will do anyway.
This is the tradeoff that is made in the H4 system to create the sharp cutoff that the H4 is famous for.
The difference of the halogen bulb being omnidirectional and the LED projects side to side is not a problem.
The LED is more efficient in a rectangular headlight and after all the beam pattern is horizontal anyway.
The arguments that a LED bulb will not work in a halogen reflector are no longer valid.

The bottom line is, on a dark country road, I can see more than the necessary 100 yards down the road on low beam with either the F2 or F3 design without glaring opposing traffic.

For the record.
The F2 and the F3 could improve focus with a little more wafer thinning.
The process that removes the excess backing and enables the chip manufactures to squeeze their chips into thinner packages.
This would impact yield but would also improve thermal performance and sharper focus.
This may not be necessary as the current crop of LED bulbs have sufficient focus to be equivalent to Halogen bulb.

I also put the F3 into other vehicles that have DOT reflector headlights that have a stronger hotspot.
These headlights also work very well with the F3 bulb and project further than the ST H4.
Just make sure that you carefully adjust the beam pattern with any upgrade.
If your headlights are old they should be cleaned and polished.
If they are really old you might be surprised that an OEM replacement headlight housing will make a huge improvement.

Opinion: the nb35 "six pack" LED would be good for high beam, the F2 "thin LED" would be good for the low beam and the F3 "in between" LED would be a good compromise. Here I am splitting hairs so take it for what it is worth.

The recent Cougar motors "flagship" bulb is an interesting cross over. It runs at the F2 power level and housing with the bigger F3 chip.

Projector headlights loose half the available light compared to a reflector headlight.
So you will want the highest power and most lumen LED for a projector headlight because of its reduced light output.

I added an update to the first post for new readers.
Click to expand...

WOW! You know your stuff on lights!

Ever think about changing your ST name to "Bulbs and Stuff" "Lights and Lumens" " Darkness No More" ? :)

Great explanation on light options, pros and cons and very well explained. :thumb:
 
spiderman302 said:
The F2 and the F3 could improve focus with a little more wafer thinning.
The process that removes the excess backing and enables the chip manufactures to squeeze their chips into thinner packages.
This would impact yield but would also improve thermal performance and sharper focus.
Click to expand...
If, by "thermal performance" you mean cooling, I thought that a thinner substrate hurts heat-sinking and cooling.
 
I was referring to the glass not the copper. It gets the hot part of the die closer to the copper which does conduct the heat away better.
There is more to this and I was trying to keep it simple.

Led_Glass_substrate.jpg

Ledcut1 (1).jpg
 
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Wafer thinning is a standard process after fabrication and prior to packaging. It removes most of the "glass" carrier so that the chip can be put into a thinner package. The white IC on the left is the old style package prior to thinning and in the right black IC the chip is paper thin.....
So in the above picture imagine the gray by the arrow getting totally removed on both sides. Better focus.

ChipSize.jpg
 
970mike said:
I tried a set of these. there is too much red showing in the reflector so I will stick with the F2 bulbs.
Click to expand...

I never really thought about the color of the bulb base showing in the reflector as my F2's are a silvery color vs the red in these bulbs or the black and blue in others.

Does the red come thru when the bulb is on or just more so when the bulb is off?
 
Obo said:
I never really thought about the color of the bulb base showing in the reflector as my F2's are a silvery color vs the red in these bulbs or the black and blue in others.

Does the red come thru when the bulb is on or just more so when the bulb is off?
Click to expand...
It shows up both when the bulb is off which is no big deal, but when the light bulb is on it reflects bright red at some angles which is a big no for me. I can see some officer thinking you are trying to be a law enforcement officer.
 
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Well after pouring thru this thread a few times tring to comprehend all the technical data and seeing the dizzying array of choices on Amazon,with huge price ranges, and even wildly different pricing between Amazon US and CA, this KaTur brand one popped up for under $40 CAD.


So I bit and hope it works out :confused1:
 
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