A new Autoexpress headlight bulb test H4

[raj55]

Here is the link.,
http://www.autoexpress.co.uk/car-maintenance/60969/headlight-bulbs-tested

It is a pity, that they did not test the long life and eco friendly bulbs since they are used more often now because the bulb change in most modern cars has been very difficult. One has to offer blood, sweat and tears (and a broken knuckle) to change bulbs in modern cars.

 

[-Virgil-]

And once again, look at that, the winningest bulbs are the ones produced by the company whose light tunnel was used for the tests. That doesn't necessarily prove (or disprove) anything, but it keeps on happening that way: when AutoExpress uses the Philips facility, the Philips bulbs win. When they use the Osram facility, the Osram bulbs win. Taken as a pattern, it's a trifle suspicious to me. I also have an issue with their having aimed the lamps "to legal glare levels". That doesn't mean anything, because the "legal glare level" is expressed as a maximum allowable intensity at several points and zones above horizontal, so "adjusted to the legal glare level" comprises an enormous range of aim angles, most of which are far too low. They should have aimed the lamps to standard 1% down, which is an objective and repeatable and realistic figure.

I don't know what changed at AutoExpress, but years ago they did much better bulb tests. They measured and reported on each bulb's filament geometry, they gave intensity figures for several crucial points within the beam for each bulb (and not just a meaningless single merit figure), etc. Perhaps -- and this is only a guess -- their advertisers did not like them revealing quite so much about what bulbs are good and what bulbs aren't so good?

(The last time these same issues were raised about an AutoExpress bulb test, it caused someone from AutoExpress to come on here and issue rebuttals and refutations. I wish they had taken the objections to heart and at least tried to address them.)

 

[raj55]

And not to forget, that the competition scored less because of "uneven quality of light out put" between the two bulbs. Are big manufacturers really that bad regarding quality evenness? Summarizing, according to Autoexpress, looking at their recent two years tests, we should buy Philipsfor H7, and we should buy Osram for H4. Now both are happy!

 

[Gregozedobe]

And not to forget, that the competition scored less because of "uneven quality of light out put" between the two bulbs. Are big manufacturers really that bad regarding quality evenness?

If they had some "dud" samples surely they should have followed up to see what %ge were less than good by buying several more of the suspect models. They might be 50% below par, or 10% or even 90% duds, but as consumers we have no idea.

 

[-Virgil-]

And not to forget, that the competition scored less because of "uneven quality of light out put" between the two bulbs. Are big manufacturers really that bad regarding quality evenness?

In my experience (and a lot of bulbs cross my test bench), no, the major makers are quite a lot better at quality consistency than the AutoExpress test implies. It looks to me as if "Oh, this bulb made by the company whose light tunnel we're not using is really great, except for…disappointing inconsistencies!" is being used as an unverifiably vague weasel provision, and I think that's a shame. Makes the test look unreliable, to me.

 

[hokiefyd]

I don't know what the "inconsistencies" are that the article mentions, but I will say that I've been disappointed in a number of H4 bulbs I've bought and installed in my 2008 CR-V. The article mentioned a blurry cutoff when using the Philips XtremeVision. I have noted before that I have a pair of Sylvania Xtravisions in H4 at home, and they definitely have a "handedness" to them. That is, if I install bulb A in the driver's side and bulb B in the passenger side, I might get a really wonky cutoff from BOTH lamps. One lamp may have no step to it at all (okay, because it's VOR), but the other one may have a very large step of diffuse light, so there's no real hotspot. But if I switch them and install bulb B in the driver's side and bulb A in the passenger side, both lamps produce a decent cutoff (though it's still not exactly the same).

The same is true of the Philips XtremePower bulbs I have AND the same is true of the Philips VisionPlus bulbs I just recently bought on clearance at Kmart. No, the bulbs aren't burning out that quick, I'm just trying different bulbs to see if any one brand or model is more consistent than the other. And I've found that it's not. For the bulbs I don't have installed, I have a "D" and "P" marked on the packaging, to denote the driver side bulb and passenger side bulb (so I don't have to switch them after installing if I get them wrong).

I suspect that the H4 bulb itself is most prone to this. From what I can tell by looking at the bulb's glare shield and how it's spatially oriented in the lamp housing, that shield has to line up nearly EXACTLY with the "cut lines" on the lamp housing for that functionality to be effective, and for the sharp cutoff to be intact. I've found that the consistency in this respect, even with top-tier bulb manufacturers, is not that great. The only bulbs that have produced two cutoffs that are exactly the same in this car were the OEM HB2 long life bulbs (from Philips).

 

[bluetoes591]

Their comparison of two bulbs doesn't make for much of a sample size. Surely a half dozen bulbs or more would have given a much better indicator of the consistency.