Driving vs Passing lights -- LED

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Camarillo, Ca
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Passing lights are NOT fog nor cornering / ditch lights. Passing lights must have cutoff to prevent glare. Passing lights are aux low beams.

Read carefully….

------------------------- ( begin rules )

There is no federal regulation of driving, passing, or fog lights; the California Highway Patrol is therefore authorized to establish requirements for such lighting Auxiliary Driving and Passing Lamps.

California Vehicle Code 24402. (1959 to present) (Your state rules may differ - but pay attention to the definitions here)

(a) Any motor vehicle may be equipped with not to exceed two auxiliary driving lamps mounted on the front at a height of not less than 16 inches nor more than 42 inches. Driving lamps are lamps designed for supplementing the upper beam from headlamps and may not be lighted with the lower beam.

(b) Any motor vehicle may be equipped with not to exceed two auxiliary passing lamps mounted on the front at a height of not less than 24 inches nor more than 42 inches. Passing lamps are lamps designed for supplementing the lower beam from headlamps and may also be lighted with the upper beam.

24403. ( fog lights follow under a different rule )

(a) A motor vehicle may be equipped with not more than two foglamps that may be used with, but may not be used in substitution of, headlamps.

(c) On a motorcycle, the foglamps authorized under this section shall be mounted on the front at a height of not less than 12 inches nor more than 40 inches and aimed so that when the vehicle is not loaded none of the high-intensity portion of the light to the left of the center of the vehicle projects higher than a level of four inches below the level of the center of the lamp from which it comes, for a distance of 25 feet in front of the vehicle.

---------------------------------------- ( end of the rules )

Wow what a missed opportunity here. All you read about is driving and fog lights......

Now what is a passing light ?? Where are the passing lights? Who makes and sells passing lights? -- Nobody? Since 1959?


I use low beams 98% of the time and I can have an auxiliary low beam to be used at the same time as the low beam !!!

Like all the time!


Wake up lighting industry! You missed the boat again!

----------------------------------------

So a long time ago when I was riding with halogen lighting,
I added extra led driving lights on my over the mirror mounts and fog lights to my forks.

These lights did improve the lighting situation until I upgraded to H4 (F2/F3) LEDs for the main lights.
After which these extra lights did not make much of an improvement and fell into disuse.
They had become merely ornamental lights.
I removed the 4 inch fog lights from the forks because they kept rattling loose.

150k miles later I noticed that the over the mirror lights were vibrating more than usual.
Upon inspection I found that the over the mirror mounts were only attached to the plastic faring which had cracked.
I glued the mounts with ABS cement and started to look for better lights that were smaller.

Yes there are bigger and brighter driving lights but I wanted something in the 2 to 3 inch range to keep the weight down.

I decided that I wanted a spot (pencil beam) since the led headlights that I have does a great job lighting up the road.

The very small 2.5 inch driving lights that I really liked were not bright enough.
They measured 25 watts, 640 lux @ 18 ft, but the shallow reflectors did not capture enough of the light for the spot and the spot was the wider of the group.
This 2.5 inch light would be a better choice for you if you spent most of your nighttime riding on the beloved curved roads.


But if you ride on the open range straight roads where the deer and antelope play you might want a tighter pencil beam spot.
I found these two 3 inch driving lights that have a tighter brighter spot, both at 30 watts, 1500 lux @ 18 ft, with deep reflectors which makes a narrower beam.



old_new_setup.jpg

The lights on the left was the old setup and the lights on the right are the new improved set up.....
The old 10 watt spot measured 470 lux @ 18 ft.
I had used the Run-D lights as an Alley or ditch lights.

98% of my riding - I can only use the low beam.

So I need to find a passing light, which according to California rules is an aux low beam.
A low beam does not have glare.
A passing light would be a pencil/spot/driving beam that has a sharp cut off. No glare.

Most cornering lights on the newer cars have glare so they are not passing lights.

No one makes such a light or advertises as such!!! Again, what a complete missed opportunity.

I would prefer a reflector design passing light since they are more efficient.
Some reflectors that I found, that might be a passing light, have a sloppy cutoff.

But there are some projector aux fog lights that might work, but they are half as bright as my low beam.
I like this one at 17 watts, 850 lux @ 18ft, which I am going to try but, it will take 4 of these to complement the H4 LEDs light level.
I only use the low beam mode with this light. There are other similar lights that are dual color. ---( I do not like yellow light at night, just my preference.)


I am testing with only one on the side of the driving lights. I have a few more other lights on order to test in the future.

So I have stirred the pot, lets see what we can brew up……
Put yer thinking caps on...

Just to be clear I am talking about a concept not a particular product....

----------------------------------- edit...

example found down at post #20 (and now #43 and #44). But do read this thread since there is a lot of information presented here.

3E Passing light

-----------------------------------------
 
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Excellent post! :thumb: Please keep 'em coming.

I have a pair of Rigid lights I haven't installed yet.
 
So there is some confusion between low beams and fog lights.

Both of these lights need to have a sharp cutoff, to prevent glare.
Cutoff is a win win for both the driver and the on coming driver.

Both lights can be wide, wide spot, spot, or a mix of patterns.
DOT low beams are usually a mixed pattern but with a strong spot.
Fogs lights are usually a wide pattern, or a wide mix.

Low beams are mounted as high as possible, but just below your line of vision.
This is the most effective location as it creates flat lighting with the least shadows and the least driver glare.
A high mount also helps project the light furthest down the road.
Reflective material projects back to the source, so this arraignment helps the driver see safety reflectors sooner.
But this reflection is a problem in fog.

This is why fog lights are mounted as low as possible, to reduce the excessive reflection from water droplets.
It is really the offset location of the lights, not the (yellow vs white) color of the lights, that reduces the reflections.
Fog lights since they are mounted low will also create shadows, which will improve 3d perception of the surface of the road. But being low, the light will not project as far as your higher mounted low beams.

The yellow filter is about reducing blue light scatter, not reflection.
Blue light scatters and creates that distant dim haze.
It is why the sky is blue and not black.

Most fog lights are wide angled to help light up the sides of the road, so that you can see the curb, or the painted lane lines, or edge of the road better. You cannot see very far in heavy fog anyway, so spots are not as effective.
Fog lights make good cornering lights or ditch lights or are good lights for city streets.

So it is really the mounting location, high vs low, that differentiates the low beam from the fog light.

A passing light would be a good fog light, with a sharp cutoff, mounted high next to your driving lights.
The light pattern would be a choice between wide, wide spot, or spot or a mix depending on where you need to improve your low beam pattern.

Lots of options here. If they were more available to us. Hint hint. ( 3 inch lights at ~ 30+ real watts ( 4000+ lumens ) each.
I do like my current set up in post #1 but it may change if I can find a better option. Still looking.........

It would also be good if vendors would publish the actual measured current (amps) @ volts, that the light uses and show the actual beam pattern.
 
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So there is some confusion between low beams and fog lights.

......

Lots of options here. If they were more available to us. Hint hint. ( 3 inch lights at ~ 30+ real watts ( 4000+ lumens ) each.
I do like my current set up in post #1 but it may change if I can find a better option. Still looking.........

Very en-light-ening, but my head's still in a fog. :)
 
Get a small pocket flashlight and go out and stand 20 feet behind any parked vehicle.
Hold the flashlight at waist level and point it toward the rear reflectors.
Now raise the back of flashlight up to the bridge of your nose.
Look over the the flashlight and hopefully you will see the light.

Retroreflector
 
So I need to find a passing light, which according to California rules is an aux low beam.
A low beam does not have glare.
A passing light would be a pencil/spot/driving beam that has a sharp cut off. No glare.

Most cornering lights on the newer cars have glare so they are not passing lights.

No one makes such a light or advertises as such!!! Again, what a complete missed opportunity.
My guess is the lighting industry has NOT missed this opportunity - perhaps a lighting company that specializes in niche markets has, but overall, no. You are far more knowledgeable about lighting and demand more than most folks. Go to any off road 4x4 store - their lights are all advertised as the brightest. Try to find beam specs. Cannot be done by us laymen. Even your recommendations on Amazon show little in the beam shape or distance. Go back a few years (maybe 30 or 35) and look at the Marchal, Hella, or Cibie headlights for cars. Their brochures displayed beam shapes and angles as well as projection distances*. Try to find that information for any of today's offerings. Maybe Clearwater provides this, but for their prices, they should.

My point is there is not a big market for specialized passing lights and no education (outside of this forum) for us laymen. Keep on teaching us, and maybe we can make it worthwhile for a small manufacturer to make these luminaires.

*Even then I was cynical and assumed there was some exaggeration, but still, the info was displayed.
 
there is not a big market for specialized passing lights

That is only because they are not selling any lights with that concept.
Except Harley, but I think they lost the importance of this light, It is now just an image thing and they never did it right.
Motorist do not know that a fourth set of lights (passing) is a legal option. (read first post)
You can not use driving lights in traffic due to glare. Fog lights which you can use in traffic, but they do not project far.
The mythical passing light can be used to supplement the low beam as a low beam. There are a lot of options here.

I have been using the 1.3 inch Exzeit mounted high, with the low beam and adjusted as a low beam.
I walked down the street and looked back as if I were an opposing driver and saw very little glare from the extra lights.
I was surprised how much these lights add visibility to the road and the sides of the road. This makes them useful.
But I still expected to get flashed by other drivers, but that has not yet happened.
That is because this particular light really does not add that much more light far down the road.
The thing is, I know what the design needs to be to do it right. So I know what I am looking for, just not finding it.
The intent of this thread is to find or make a better solution.

Yes, I cut my teeth on the Cibie Z-beam, fog, and driving lights back in the day.....
I spent a lot of time running around the desert at night in my Jeeps using different light set ups over the years.
 
The intent of this thread is to find or make a better solution.

Yes, I cut my teeth on the Cibie Z-beam, fog, and driving lights back in the day.....
I spent a lot of time running around the desert at night in my Jeeps using different light set ups over the years.
I agree with you. I'd even settle for teaching idiots in cars how to pass properly...and that does NOT include pulling back into my lane with 3 feet to spare in front of my bumper.

I have a pair of Cibie Z-beams on my '89 Honda Accord and they still do a good job lighting the road. Just put some Evitek F3's in them....
 
quadLEDspot30w.jpg


I was a little disappointed with this 3 inch projector quad pod with the bug eye lenses (#4) since I had high hopes that it could have been the best.
It is brighter at 30 watts but it spreads out the light too much, so it has a little less peak intensity (750 lux) than the 1.3 inch single led projector Exzeit (#3) (850 lux).
However this quad light may fit your needs without any modification as it puts more light on the sides of the road with its larger pattern. It has good cutoff.

Since the pattern was not sharp, I took it apart and modified it to improve the focus.
I removed the gasket and placed two stacked washers to make a 0.062 inch gap between the frame and the lens at each screw hole.
I had to get four longer M4-12 SS flat head screws. I used silicone glue to seal the gap and water proof the light as well as to hold the 8 washers in place.
The lens is not round so make sure that it is put back in the same orientation.
This focus shift made the beam pattern smaller and brighter (1,300 lux modified).
It has some artifacts that will require internal masking. This light has potential but it is too much work for most users.

I am posting this modification to demonstrate how just changing the beam spread changes the peak intensity.
The data for this will be shown on item (#4) posted below, which is listed twice (before and after focus shift).
This one has elliptical lens that spreads out the light, unlike others that have round lens that create square beams.
I think the thin horizontal rectangular pattern is more useful than the square beam patterns created by other lights not shown here.


quadLEDspotMod2.jpg
 
Let me digress here. This is important for you to understand my goal.

Mesopic vision is where our eyes switch from using your cones to your rods. That is where day time vision switches to night time vision.
Night time Rods are slow, have no focus and no color vision. Day time Cones have fast response, gives us focus and gives us color vision.
Our cones work down to 30 lux!
At 10 lux there is about 30% loss in color sensitivity. At 1 lux there is 70% loss.
So 10 lux is considered the minimum level of light for color vision.
This should be the minimum level for safe night driving.
We have a problem here!
The minimum safe response and stopping distance for 70 MPH is 300 feet.
If you look at the light levels provided by halogen low beams. They provide 2.5 lux at 300 feet (orange box) which will be 10 lux at 150 feet.
It will take 4 halogen bulbs or 1 LED bulb to get to 10 lux at 300 feet (yellow box) . Two LEDs or 8 halogen bulbs will give you 20 lux.
Our Cones work down to 30 lux where it starts to roll off. If you are older you need more. This is where lens design, focus and beam pattern are critical.

So my goal is 10 plus lux at 300 feet with the least glare. Just the length of a football field!
This would be a aux low beam that would be close to the range of 42,000 to 75,000 cd peak or more.

A side note for your reference. -- Street lights put 10 lux on to the roadway under the light. Now, you know why.

Our lighting rules were defined back when we had tungsten lighting, small generators/alternators and poor optics.
However the rules were cleverly written and define only minimum illumination and maximum glare.
They left holes that allow for improvements! Today we have LEDs that can give us the light that is necessary to drive safely at 70 MPH with less power.
We also have better optics that makes a sharper cutoff that protects opposing drivers from glare.
 
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In the table below is the data that I measured at 18 feet, the setup I have in my garage, and the 25 feet data is taken from some vendors or other testers. The 300 feet column is calculated. The blue line is the ST1300 levels with the upgraded led. Because of the beam spread, it does not get to 10 lux at 300 feet. So adding even the smaller Zoom and/or Exzeit lights will get levels up to where they need to be at 300 feet.

Do note that the standard LED low beam is at 1840 LUX which is my reference point for an equivalent aux low beam.

The green boxes and line numbers are referenced in Posts above table.
Other data I have added is for your comparison.

So, Yes, adding Aux passing lights is a good thing and is necessary for your safety.

lux300_led4.jpg
 
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Spidey, do you have an opinion on these?
  • Watts: 29
  • Amp Draw: 2.07
  • LEDs: 4
  • Raw Lumens: 3168
  • Lux @ 10m: 388.94
  • Beam Distance: 197.2m
  • Peak Beam Intensity: 38,894 cd
  • Rigid Industries 202213BLK D-Series Pro Spot Light
 
I bought these projectors a few month ago and yes, they spread too much on the top and bottom of the road.
A rectangular shape would have been better.
I am tempted to follow your modifications but I am worrying about water proofing, they are very exposed to elements.
I installed them under the crash guards and they are doing a good job for illuminating the side of the road for animals and that's why I got them.
Deer country!
Design is the key and there is still some room for improvement.
To be fair, you got a lot of tech for a very affordable price and it's hard to complain after all.
 
Larry:

From what I can tell from their web site, those will make very good Driving lights.
They would not be good for Passing lights since they have no cutoff.
 
Mounting a fog light on the front forks. FYI.

microLEDfog.jpg

1.3 inch fork lights -small

The front fork tubes in our case move.
This puts a lot less stress on the plastic mounting location that is constantly bouncing.
The nice thing about the Zoom lights is that they are extremely small and very lite, which will put less stress on this mounting location.

This light is bright enough for fog. You do not need an over powering light for fog.
At 18 feet it measures 500 lux each at 15 watts narrow fog pattern.
This tiny Zoom light is item number 2 in the above list.
Silicon glue seals the wire hole. The wire is 3 feet long.
If you wire up the red wire (white fog) to the running lights then just put the switch on the yellow wire (yellow conspicuity).
When you turn on the yellow the white will automatically turn off. It does not work the other way.
I mounted them upside down so I can use the (low) white for night/fog mode and (high) "in your face" yellow for day mode....

Low mounted fog lights do have two purposes. The one that everyone knows is for fog. But the other is that it creates shadows.
In photography we call it modeling light. The shadows improves your 3D perception of what is on the road.
Pot holes and rough surfaces will stand out better.
 
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Mounting a fog light on the front forks. FYI.

microLEDfog.jpg

I mounted them upside down so I can use the (low) white for night/fog mode and (high) "in your face" yellow for day mode....

I got a set of these last night. They are indeed tiny! They also have a fan in the back.
First observations: When I have them oriented this way the white light projects higher, the yellow light lower. May be how the dual chip is installed.
Cut off is very distinct. I was surprised at how much light they threw at a distance.
The lens can be rotated if you loosen the ring. I'm going to see if rotating it and the " || " part in the lens's center adjusts the horizontal aim or inverts the yellow/white arrangement.
 
The lens is elliptical (not round). Rotating it will distort the pattern. There is a notch in the ring and a tab on the lens for alignment.
The only way to flip the yellow / white is to mount it upside down the way I did. Have fun with it!
 
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Unfortunately, I have a box full of junk lights, that should have worked, but due to poor attention to details, they failed!

--- well almost -- A Passing Light !

This is the best I have found so far and I put the clue in the data table.
It is not exactly what I am looking for, but it is a big step closer.
This one has very good cutoff, good throw and good simple pattern.
It's brightness will compliment the LED Headlights @ 1850 lux (55,700cd) each. (see red box above)

3EdrivingLight1.jpg


3E Passing Light

I will be mounting it up soon and we will see how it works out.
It is bigger than I would like 4.6 inches wide and makes mounting with the driving light a tight squeeze on the bike.
I would prefer it to be in the 3 inch form factor and 30 watts or more.

This 3E light is the best implementation and should be used as a design reference.
It just needs some other small tweaks to be awesome….
There could be many options here!

So let’s talk about Passing lights.
They will be wanted and used more than the other aux lights!
This is nothing new. Just a legal light option over looked…..
 
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