daytime running lights on my 2005 Expedition

Actually, the "mask effect" occurs when the output of the artificial light source is close to being equal to the back lighting of the back lit object. Since daytime back lighting conditions are constantly variable, the DRL output would also need to be constantly variable in order to to eliminate the condition from occurring at any given point in time.

In military airplane light masking applications, they were implemented with rheostats to change the intensity of the artificial light source as required to maintain minimum conspicuity for the longest amount of time. Often the enemy heard them before seeing them.

Are you sure that activating the DRL isn't just a simple BCM software configuration change that your dealer could do?

The thing about DRLs is that they are not there for people to find Waldo or say mom or dad or cousin Fred. They are there so that you can determine that someone is there without determining who.

So your Waldo analogy, while interesting, doesn't really apply.

As far as the DRL rule coming down to winners and losers, that's true of everything. Unfortunately, there are tradeoffs in everything we do.

Jeff

So your idea of a "tradeoff" is to allow motorcyclists to die (in ever increasing numbers) so you can be "conspicuous" with your headlights on while driving around in your 3-ton SUV?

Sharon, please don't put words in my mouth. And, I don't have a vehicle that weighs over 2 tons, with me in it. If I had an SUV, it would a model, hybrid and all, that many people see as taxicabs in NYC.

My idea of tradeoffs is that we learn about under which conditions DRLs decrease the total number of deaths and learn about under which conditions, they increase the number of deaths. Then, DRL laws are implemented, accordingly, to cut down highway deaths as well as other things that increase the safety of those negatively impacted by DRL laws.

Everything we do has tradeoffs. Riding bicycles and playing soccer or hockey, are great for health, but you risk a head injury. Sorry, that's life. With hybrid vehicles, they are silent when they start moving. An obvious issue for those who are blind. Yet they save fuel and reduce green house gases.

Likewise, putting airbags in cars have tradeoffs. Death rates do go down. But, cost goes up. So does risk of injury in certain types of crashes, especially for people not using their safety belt.

Before passing new laws and regulations, the pluses and minuses have to be weighed.

Jeff

I'm not "putting words in your mouth", merely pointing out the fallacy of your pseudologic; trading dead motorcyclists for fender benders is condoning mass murder just to support a half-baked notion. The stats of bike riders having an increasing number of accidents every year are REAL, while the stats on the efficacy of DRLs in the lower 49 US states is tenuous at best - mostly stuff that was collected by GM and its minions, and presented to USDOT/NHTSA as ?fact?. I don't ride any more (due to inner ear problems, and I'm also NOT Sharon; she's my wife), but if I did still ride, I?d see about getting biker organizations enter into class-action lawsuits to sue GM?s collective ass off, for promoting those damned DRLs here in the USA, AND also to sue DOT/NHTSA to at least allow the 42 states that once had laws AGAINST driving with lights on in the daylight in clear weather (excluding funeral processions) to re-gain control over their own lighting laws.

Jeff wrote in news:6g8ki.620$475.87@trndny04:

Bullshit, years ago I lived in California and drove back east, and on holidays these DJ idiots would encourage everyone to turn on their lights and it was a brutal after a few hours of looking at headlights. Yea, I know driving lights are different but they still have the same effect. What is needed is automatic headlamp sensors to turn on low beam lights when the ambient light drops to a pre-determined level and it should have a manual override which after each use would default to turn lights on the next time the car is driven. Everyone could live with that and people like you could manually turn on their lights in daylight just to be obnoxious.

Agreed! I have two vehicles with automatic headlights (AND TAILLIGHTS AND RUNNING LIGHTS) controlled by a photocell sensor that turns the exterior lighting on when starting up in the shade, or if it's overcast/raining, or if it's NIGHT! These automatic lights can also be turned OFF whenever I choose. That concept makes perfect sense to me. The idea of running around in sunny broad daylight with turned?on automatic lights that CAN?T BE conveniently turned off make no sense whatsoever to me; if I'm no longer able to see 2-ton and 3-ton vehicles coming toward me unless they have their headlights on, I'll turn in my driver's license.

First of all, you will notice my my last sentence, which concludes, "the pluses and minuses have to be weighed."

That includes accurate data and taking all factors into account.

I never said anything about trading motor cyclists' lives for anything.

I never said that the GM stats are accurate.

Obviously, if the USDOT were to make a decision, they would have to use accurate stats.

So you clearly have a problem with motorcylcists getting killed because of a law. So do I.

I never said anything to suggest otherwise.

jeff

What is needed is collecting accurate statistics and making informed decisions based on the data.

Jeff

The REAL stats are there about the motorcycle accidents increasing, and NHTSA acknowledged the causality of cars & trucks with DRLs nearly 10 years ago. Since then, DOT/NHTSA has seemingly chosen to ignore the stats for these many years (maybe a new free Escalade for a few key players every year; who knows?), but as the number of automatic DRLs on the roadways in the USA increase (majority by GM), so do the motorcycle accidents. This is largely due to the "Where's Waldo?" analogy you previously dismissed, but the truth of the matter is, as the number of vehicles with DRLs increase, there will be a "tipping point" where it will be the same as if NO vehicles had DRLs, simply because no vehicle, OR GROUP OF VEHICLES, will ?stand out?, since all the vehicles will be equally visible again ? except MOTORCYCLES ? since the frontal profile of a motorcycle is about ½ that of a ?two-track? vehicle. The conspicuity that motorcycles once enjoyed ? by being the ONLY VEHICLES that had daytime lighting - will be effectively gone. The only thing we?ll be left with after the tipping point is a ?sea of lights?, where all drivers will be vision-impaired due to the constant sea of light (and some of them will be quite unhappy about it). A little reading about DRLS, pro and con:

also stuff about SRS air bags there, which is another darling of the nanny state mentality.

Thanks.

Too bad you don't have links to the real stats.

Jeff

About any real NHTSA stat you'd want is contained herein; you just have to be smart enough to know what to ask:

The NHTSA has been collecting studies and statistics since at least

1995. They've yet to publish any conclusions or make a final DRL rule.

It would be a mistake to use DRL's alone to ascertain the presence or distance of an object. For example, certain Saturns and Oldsmobiles have DRL spacing that are "inboard" at 10" to 12" apart. Therefore, they "appear", by light alone, to be a much farther distance away than they actually are. Make a left turn in front of one of those and you may get a big surprise. It is preferable, in my opinion, to have an environment that provides the best capability to observe to details of the vehicle itself vs. a couple of lights shining in your eyes that obscure some of that detail. And Saturns especially seem to have painfully bright DRL's that "seeing" the actual car for many people is difficult.

I would disagree with your discount of the need to be able to observe the finer details of the overall driving scene.

GM went waaaayyy beyond simply "promoting" DRL's. They went so far as to "mandate" them. And they did so without the authority to do so and beyond any law requiring them. GM owners had no choice in the matter other than buy a vehicle from a competitor (which was dumb). Other manufacturers, at least, give their customers the option of having the DRL's activated or not. Interestingly, you don't see many Fords, Chrysler/Dodges, Nissan, BMW, Mercedes, etc. going about town with the DRL's on, even though they are available to the customer if they choose. Probably with gas at $3.00 a gallon, customers don't want the extra fuel consumption that comes with the added electrical load.

Jeff