Light bulb question -- Daniel Stern?

Sylvania primarily lists *NOMINAL* output, not actual, in their materials. Nominal output is the legal spec contained in Federal code 49CFR564. The spec for each bulb contains a nominal flux as well as the allowable tolerance range as either a plus-minus percentage or an absolute maximum. Take a look for yourself here:

and you'll see howcoincidentally all those Sylvania bulbs just happen to (be claimed toproduce) exactly the nominal value, right on the nose. Quoting nominalvalues is the same as saying "These bulbs are all legal". Sure they are,but nominal values do not describe the differences in performance amongstthe different bulbs. Can you think of a reason why Silverstar (whichproduces near the high end of the legal output) and Cool Blue (whichproduces near the low end) would be quoted at nominal rather than actual?I can. I can also think of a reason why Sylvania would field a gimmicky,expensive, short-lived, low-performing Silverstar for your 300M but *not*a higher-performing, non-gimmicky, longer-lived, less-expensiveXtravision.

DS

All the above is fine.

Corrections below in all-caps

Try

The Sylvania Silverstars make your headlamps put out *less* light. The impression you got that they're "brighter" is nothing more than an optical illusion.

So no, it's not a shame.

Another victim of inadquate headlights here.. 97 Sebring convertible. So I replace the headlight bulbs with Xtravisions and make sure they're aimed correctly. I'd like to find a set of aftermarket fog lights for the car.. only mounting location is the factory holes in the bumper. Looking to improve lighting right in front of the car, ditches and road markings. Would also consider a dual filament light to improve distance lighting with high beams.

Just trying to see better at night..

I have used high wattage bulbs in other vehicles.. I am led to believe that it's not a good idea with these headlights.. why?

Thanks,

Jim

That's about all you can do with those headlamps.

Bosch Compact 100s have a particularly useful beam pattern for what you're trying to do and should fit the factory holes without much difficulty. They are 100mm (4") diameter.

There is exactly one dual-function fog/driving lamp worth a damn. It is enormous (8-3/4" diameter) and works well on very large vehicles used off road. For on-road use, a low-mounted driving lamp is only slightly less useless than a high-mounted fog lamp.

The wiring is barely adequate for stock wattage, let alone overwattage,though that can be fixed with relays and heavy-gauge wires. The unsolvable problems are:

-This is a small headlamp with a reflector made out of low-grade plastic. It cannot handle the extra heat of an overwattage bulb and will deform, melt and/or burn.

-The beam pattern is poorly formed. There is too much uplight and too much upward stray light, and glare is relatively high -- all with a stock bulb. If you put in an overwattage bulb, you will not make the beam pattern any less worse, you will only aggravate the glare and backdazzle problems.

-No decent factories manufacture overwattage 9007 bulbs, so what's available is crap made in the 3rd world. Filament placement is stinkin'; fractions of a millimetre make enormous differences in beam pattern formation.

So, don't use 'em.

dastern "at" danielsternlighting "dot" com if you have questions or anything.

Daniel, I don't understand. I have Silver Stars in my 97 Cherokee Sport and My 96 Plymouth Grand Voyager. They are definitely a big improvement over stock. Why do you say they put out less light and it's only an illusion that they are brighter?

Well.. lets not forget buff/polish the plastic lenses every few weeks to remove the haze.. *nice* job Chrysler..

I'll look into them..

Lets hear it for Oscar the Super?.. I considered them before I realized that they would require the 'saws-all' install method.

Appreciate the answers.. one more question. At what voltage drop do you consider re-wiring the headlight circuit?..

Regards,

Jim

They start out putting out more light (this is why they don't last too long), but then Sylvania puts a coating on the bulb to make it look a bit blue. This may make you think it "looks" brighter, but tests confirm that the coating significantly reduces the bulbs output. Some coatings (most coatings) cut light output in half. "Believe it or don't".

Richard.

Yeah...if you're having to buff them every few weeks, it's time for new headlamps. What initially hazes over is the hardcoat on the lens. When you polish that away, the polycarbonate lens is no longer protected from UV and abrasives, and the haze comes back faster and worse every time. (Here all this time you thought you owned a Chrysler; turns out you've got a cataract!)

Yep, that's the one.

Well, remember, light output drops exponentially, not linearly, with voltage drop. Small voltage drops = large light losses. The formula for determining the change in light output with a change in voltage is:

lumens @old volts x [(new volts /old volts) ^3.4] = lumens @new volts

So for simplicity's sake, let's take a 9007 low beam rated 1000 lumens at

12.8 Volts and plug in different voltages: 10.5V : 510 lumens 11.0V : 597 lumens 11.5V : 695 lumens 12.0V : 803 lumens 12.5V : 923 lumens 12.8V : 1000 lumens

On Mon, 1 Nov 2004, it was written:

Exactly. This "Definitely a big improvement!" stuff is nothing more than the Slick-50 effect. ("Of course I can see better! No, really, I can, it's a vast improvement! Huge! Whaddya mean it's an illusion? Shut up, it is not! I just spent $45 on these light bulbs; of COURSE I can see better!")

Nope. They aren't any such improvement.

Because they put out less light and it's an illusion that they're brighter.

This seems to be such a common problem, is there any way to restore the UV protective coating once you've got the lenses buffed up? Bribe you local eyeglass emporium?

nate

There's likely to be more going on than the Slick-50 effect: first, our eyes are really good at seeing at various light levels; that's why learning to take pictures with manually-operated cameras requires some learning. We can easily be fooled into thinking things that are much brighter are actually dimmer and vice versa.

Quick digression: for last year's State Science Fair, one of the competitors studied the effects of tinted shooting glasses on accuracy. He had a dozen or so participants, ranging from people who'd never fired a pistol before to a member of the Albuqurque SWAT team. *Everybody* was convince that they saw the target more clearly with yellow tinted lenses. *Nobody* actually shot better with yellow lenses, and most shot better with clear lenses. Moral: everything you think you know about how well you see, and under what conditions, is wrong.

I'm going to hazard a guess that the Silverstar lights have a narrower spectrum than stock or Xtravision (which is what I would expect, since I'm under the impression that they're just a standard halogen bulb with a blue filter), and that this provides the illusion of greater brightness and visibility. That and the Slick-50 Effect, of course.

Nothing that's worth the effort and available to a DIYer, no. The original hardcoat is applied and UV-cured under cleanroom conditions; there's nothing in an aerosol can that'll even dream of coming close.

ISTM that this is a wonderful opportunity for an aftermarket product. Probably of the type that would only be sold to paint shops etc. but still...

nate

Here's what some people use:

Not sure if they have the Dr. Stern stamp of approval, but they definitely prevent abrasion, give some (claimed but of course unquantified) UV blocking, and give the added benefit of protecting against breakage or chips from stones.

Probably it would be best to apply over new headlight assemblies rather than put over buffed-out old units, but that also could be done if $$ is tight (if the buffed out old ones will keep their water-clear clarity due to the added protection of the covers, which is questionable - I know that without covers, buffed out ones need to be polished every few weeks as was aready pointed out).

Obviously anything you put in front of the headlight is going to block some light no matter how clear, but I would think the attenuation is small, and as a new headlight without them ages, at some point in time, the headlight with them that was replaced at the same time will be brighter for the remainder of its life - I would think the crossover point would come within a few months of sun and blast exposure (and if the cover starts clouding or yellowing, which may happen after, say, 2 to 4 years depending on geographic location, you can always replace the covers for another $45 - cheaper than new headlight assys.).

Something to consider.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my adddress with the letter 'x')

...and here's the source:

Your attempt to give me a heart attack so I can't go cancel-out your vote with my vote is unsuccessful; to have achieved success, you'd've had to have recommended "Stongard". ;-)

(Besides, I already voted.)

Well...kinda. They prevent sandblasting, but if a large enough road rock has your headlamp's name on it, it's going to break the headlamp with or without film. Also, you have to be careful on smaller lamps; these kinds of films can trap significantly more heat inside the lamp, degrading the lens from the inside rather than from the outside.

All in all I have much less argument with Xpel than with the other.