Daytime too curiously enough. Though I suspect some of it may be the proliferation of cheap LED replacement “bulbs” being put into housing meant for halogen bulbs and never being aligned/aimed to mimic the factory cutoff.
In most the the aftermarket LED bulbs that I’ve seen, the location of the diode(s) causes light to emit from different point(s) that it would from a halogen bulb, thus reflecting differently than intended.
> “To put it simply, yes. LEDs can be used in reflector headlights BUT (and it’s a big but) if you’re upgrading the bulb, you also need to upgrade the reflector bowl. Failure to do so can blind or dazzle other people. You see, no two reflectors are the same. Each reflector headlight design is meticulously crafted based on the precise specifications of the halogen bulb it intends to use. This ensures there’s a good throw and spread of light.
Replacing a halogen bulb with an LED, therefore, throws the reflector off balance. Even minute changes will alter where the light hits the reflector and gets projected out to. Essentially, the light will end up in places it was not intended to. This is exacerbated by the fact that LEDs are a directional light source, whereas halogens are omnidirectional. Unlike halogens, an LED will not illuminate the reflector surface evenly. This has two consequences:
Firstly, by shining light only at the reflector’s sides, there’s likely to be blank, hollow, or hot spots in the light beam.
Secondly, by failing to illuminate the upper portion of the reflector, the headlight will have reduced distance projection. Instead, the light will scatter above the cut-off point and blind other drivers.“
