first road trip - headlight question, etc

[designbytes]

did my first extended road trip with my new pilot and overall was a good experience. One thing caught my attention - the headlights at low beam.

It took me a bit to figure out what was happening, but I have never seen a set of headlights that kept the beam of light so focused - particularly on the top/high dimension of the light beam. There is a definite "line" of coverage when on low beams and above that line, it nearly totally dark. Virtually no light leakage at all. At first, I thought I was seeing the line in the windshield from darker glass at the top, but no.

This was particuarly noticable and bothersome on hilly a back country roads, where my field of view (covered by the lights) kept shrinking and growing as I went up and down hills and/or round curves.

I come from a 93 trooper, so maybe headlight technology has changed significantly since then, but my wifes 05 Accord doesn't do it.

any thoughts?

[2muchfun]

I notice the same effect. Its caused by the new projector beam headlights which are, indeed, very focused (just like a movie theater). I keep meaning to adjust them up just a tiny bit...

[designbytes]

thanks...I guess I will drive a while and see if I get used to the pattern before I try the adjustment mode. (is that easy to do?)

on another "road trip" impression...

I can see I am going to be using the brakes on my Pilot a lot more than my trooper. I am coming from 20+ years of manual transmission use and am used to slowing/stopping the vehicle just by letting my foot off the gas - never using the brakes until the tail-end of the stop. I have developed high traffic "anticipation skills" over the years (!) and am only on the second set of brakes after 337K miles. [original tranny, btw]

With auto transmission, letting your foot off the gas, does nothing to slow the vehicle down unless you are going up hill. I really dislike that sensation! I am going to have to learn some new things!

...it shifts a lot more than I do as well....

old rider....new horse....;-)

[5Gs]

Originally posted by 2muchfun
I notice the same effect. Its caused by the new projector beam headlights which are, indeed, very focused (just like a movie theater). I keep meaning to adjust them up just a tiny bit...

just a tiny bit...not too much...I don't want to be blinded by you when I'm going the opposite direction!

[ctobio]

Don't "adjust" the headlamps higher. They are optimized to put light exactly where you need it- a reasonable distance far enough away to give you an apprpriate reaction time. Adjust them higher than the specification and you will dazzle people, and not in a good way.

At night, you don't need to light up the sides or directly in front of the vehicle. In fact, foreground illumination is bad because it causes your pupils to close up more, affecting your night vision. Sure, you can see the stuff you're about to run over you can't do anything about, at the expense of seeing whats far enough away!

This is why people who drive with their fog lamps on all the time are fools!

Automotive headlamps have been really crappy in the USA for years, for many reasons, not the least of which were shortsighted (no pun intended) or ill-concieved regulation by the DoT.

It's only now that the DoT and automakers are figuring out how to make a good headlamp system, and American consumers are not used to these new setups (and consumers are not being educated properly)

Projector headlamps are a great innovation. They do a phenomenal job of putting light exactly where the driver needs it, unfortunately, drivers don't really have a good understanding where they need the light the most.

[xGS]

Originally posted by ctobio

Don't "adjust" the headlamps higher. They are optimized to put light exactly where you need it- a reasonable distance far enough away to give you an apprpriate reaction time. Adjust them higher than the specification and you will dazzle people, and not in a good way.

At night, you don't need to light up the sides or directly in front of the vehicle. In fact, foreground illumination is bad because it causes your pupils to close up more, affecting your night vision. Sure, you can see the stuff you're about to run over you can't do anything about, at the expense of seeing whats far enough away!

This is why people who drive with their fog lamps on all the time are fools!

So goes the theory.

However, a study by Olson and Sivak investigated "driver eye movements at night as a function of foreground illumination. At high levels of foreground illumination, drivers tended to look further down the road. Olson and Sivak’s interpretation is that with high levels of foreground illumination, drivers tend to use peripheral vision for the foreground and foveal vision for distant points. This may be why drivers prefer higher levels of foreground illumination."

[designbytes]

Well. I am definitely a "look further down the road" kinda guy.

I find myself trying to "look thru" or beyond the scope of the projector beam all the time - around the corner of a turn or beyond the hill or dip. It seems my sense of "safe speed for the illumination" really varies or is overly sensitive according to the road topology because I am constantly going in and out of far and short reaching, high contrast cones of light. Mountain or country roads are where it is most problematic.

still in test mode, but....

I am very tall and sit high in the seat, I wonder if my higher viewing angle causes more of a problem? I find that what is "optimal" for industry usually means "works great for average folks" and probably doesn't work at all for me! :-)

[ctobio]

Originally posted by xGS

However, a study by Olson and Sivak investigated "driver eye movements at night as a function of foreground illumination. At high levels of foreground illumination, drivers tended to look further down the road. Olson and Sivak’s interpretation is that with high levels of foreground illumination, drivers tend to use peripheral vision for the foreground and foveal vision for distant points. This may be why drivers prefer higher levels of foreground illumination."

That's great and all, but did they address the pupil un-dilation (sorry, can't remember the opposite of dilation) that accompanies the greater amount of light being put down closer to the driver? I would surmise that this has a negative impact on how well the driver can see marginally illuminated items (say, a deer on the side of the road).

More light does not necessarily mean you can see better. Headlamp illumination is all about seeing what matters- this is why projector lamps are a real advantage because they put light EXACTLY where one would need it, and do it without negatively impacting other drivers with dazzle or glare. However, people underestimate their effectiveness and "help" matters by driving with their fogs on, simply because they don't understand how these work, or were trained on the crap headlamps Americans have been subjected to for the last 80 years. Remember how crappy sealed beam headlamps were? The newer headlamp systems are all about putting light where it's needed- above and somewhat beyond the braking distance of your vehicle at a reasonable speed.

[ctobio]

Originally posted by designbytes
Well. I am definitely a "look further down the road" kinda guy.

I find myself trying to "look thru" or beyond the scope of the projector beam all the time - around the corner of a turn or beyond the hill or dip. It seems my sense of "safe speed for the illumination" really varies or is overly sensitive according to the road topology because I am constantly going in and out of far and short reaching, high contrast cones of light. Mountain or country roads are where it is most problematic.

This is a real problem, actually, but I'm not sure how to bend the laws of physics and curl light around a curve.

On these mountain roads- is the use of high beams not feasable? Our high beams (at least on the '06) aren't projector housings, so they flood a great deal of light. Frequently when I drive in an area I imagine is similar to your experience (rural Western NY, due south of Rochester), I switch back and forth from high to low beams, and anticipate when to do it based on when other drivers are oncoming, or another vehicle is ahead. This might help your experience.

I am very tall and sit high in the seat, I wonder if my higher viewing angle causes more of a problem? I find that what is "optimal" for industry usually means "works great for average folks" and probably doesn't work at all for me! :-)

The change in perspective is marginal- a mere couple of inches. The light is still in the same place wherther you're 6'2" or 5'6". I can't imagine this makes a huge difference, but I could be wrong. Crouch down and see if it makes a difference.

[designbytes]

Originally posted by ctobio


This is a real problem, actually, but I'm not sure how to bend the laws of physics and curl light around a curve.

On these mountain roads- is the use of high beams not feasable?

that is what I end up doing, it just was more than I had needed to do it in my ancient trooper.

...need that "heads up" control of the light direction - as my head moves, the lights move! please invent that ! ;-) Actually, aren't there some higher end vehicles where the headlight aim do move with the car?

6'9" btw....

[ctobio]

Originally posted by designbytes

Actually, aren't there some higher end vehicles where the headlight aim do move with the car?

The Citroen DS series of the '50s-'70s had that. So did the '48 Tucker Torpedo. There's some luxury SUVs that have that today.

You probably didn't need to use your high beams as much in your old Trooper because the headlamps were flooding the road ahead.

6'9" btw....

You have 1'3" on me then... That said, was taller as you are above average, I can't imagine the change in perspective is that significant. The light is still in the same place no matter how tall you are.

[Bruce K]

I took notice to this my first day I received my Pilot. I took it home at night time and when traveling down hills or dips, my visibility was reduced down to about 2 car lengths. So I had to slow down. I took it back to the dealer the next business day and they were able to make a slight adjustment, they said there was not too much to play with. It helped a little bit, I don't drive that much at night so it's not a big problem for me. I asked the mechanic if anybody else complained about the projection beam and he said I was the only one.

[xGS]

Originally posted by ctobio


That's great and all, but did they address the pupil un-dilation (sorry, can't remember the opposite of dilation) that accompanies the greater amount of light being put down closer to the driver? I would surmise that this has a negative impact on how well the driver can see marginally illuminated items (say, a deer on the side of the road).

Rather than attempting to measure pupil contraction directly, a second test was performed to determine the distance at which an object could be identified. The test used a standard auto headlamp either alone or augmented by a motorcycle headlamp (with a sharp horizontal cutoff) that was aimed lower than normal to add extra light immediately in front of the vehicle (similar in effect to using foglamps). The different target objects were a small box and a larger wood panel, both covered with denim, and a person wearing either denim or white clothing. Different runs were performed with the targets located toward either the left or right side of the road. The result was that the extra foreground illumination made no difference in the distance at which an object could be identified (depending upon the object size and location, it would be detected only a few feet earlier or later).

In fact, any increased pupil contraction might be considered advantageous since the resultant greater depth of field could lessen the need for accommodation and, therefore, cause less eye fatigue.

[ctobio]

Originally posted by xGS

In fact, any increased pupil contraction might be considered advantageous since the resultant greater depth of field could lessen the need for accommodation and, therefore, cause less eye fatigue.

Got any links to this study? It sounds rather intriguing. I'd love to read up on it.

I still maintain that there has to be something better than fog lights to get the proper amount of foreground illumination. Fog lights aren't exactly the right thing here.

[CMasten]

I was only able to adjust my 05 headlights only so much and then gave up, they just dont put enough light out for me to see clearly at night under certain situations, i.e. rain, fog etc. I added a pair of Hella FF75 driving lights and most of the time I dont need to add them, but when I do... illumination is no longer an issue.