Reddit reviews Philips 9008XVB2 X-tremeVision Upgrade Headlight Bulb with up to 100% More Vision, 2 Pack

> How much thought in vehicle lighting is given to the effects on other drivers?

A lot of thought is given, but not all of that thought is implemented.

Glare is always an issue. There are actually new beam patterns coming into play now with huge, unprecedented divots around the glare zone. This creates a margin of safety with today's extremely intense LED lamps, which have left even the best HID systems in the dust years ago. And the huge shaded areas are meant to kind of "game" the system, as third-party, non-government testing agencies are very strict about glare.

>I'm sure intensity is a big part, but what of coloration or "strobe" rates of LEDs, etc? (Sorry if I don't know the proper terminology here.)

Unfortunately, pretty much all OEM LED systems have extremely high color-temperatures, and the marketing people love to make BS claims about the light resembling "natural daylight" and the such, when in reality, there's very little resemblance to natural daylight, and even if there were, that's a meaningless comparison. Halogen light actually best resembles natural daylight, as halogen/filament light sources are extremely good at accurately rendering color (high CRI/color rendering index). In case you are confused about CRI, think of an old town with the high-pressure sodium lamps that emit a bunch of yellow-colored light. Imagine looking at color photos in that sort of light; everything is going to appear kinda weird looking and not exactly true-to-life. That's because the color-rending index of these high-pressure sodium lamps is extremely poor.

HID systems are not as good as halogen at rendering color accurately, which some people thought could be an issue in the 90s, when HID systems first appeared in automobiles. Is accurate color perception essential to early recognition of roadway threats? The research found that nope, we don't need super great color rendition to perceive threats.

LEDs can be good at rendering color correctly, but really, the whole issue of "color rendition" is a moot point. Sunlight is the best at rendering color accurately, and halogens closely match sunlight in that ability, but again, CRI is pretty much meaningless for driving safely.

The research does show that cool-colored light is 50% more glaring than warm-colored light. We can make LEDs warmer, and reduce glare complaints, which are going up in recent years, or we can make LEDs warmer and increase intensity, and allow drivers to see further while keeping glare complaints at a constant level. Making LEDs cool-colored is just for marketing, unfortunately.

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Back to the original topic of retrofit LED bulbs: I would not suggest that anyone install any retrofit LEDs for now. The SAE is working long and hard on defining a set of standards to which retrofit LED bulbs can be built. Until those standards are finalized, I would stay far, far away from LED bulbs.


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>I have actually been extremely impressed with the function of the Spark's halogen bulbs.

Good, and you'll probably be more impressed with these:

https://www.amazon.com/Philips-X-tremeVision-Upgraded-Headlight-Vision/dp/B00U1OLOP0/ref=sr_1_5?keywords=h13+xtreme&qid=1563828609&s=gateway&sr=8-5