Great thread. Such a hard topic to really perfect, also. Any modification done will be to the standard of the owner, and everyone’s standard differs. in search of a standard, some will default to an oem, or other bar, but then we find that oem “standards” are hugely varied, and other standards have strengths and weaknesses, with so many different variables like distribution, cutoff, color temp, glare, etc..
my personal opinion .... LEDs are getting there, and even the minor differences between an led drop-in and the original halogen bulb could be acceptable depending on the design of the housing. A larger reflector assembly or projector housing would be less affected than a smaller assy. I’m a bit particular like many here, but admittedly some of the stuff i/we can halfway mod today is better than some oem assemblies of both yesterday and today in terms of cutoff, glare, distribution, etc..
BUT, I think we all mostly agree that in general, they don’t work well in most cases for proper controlled output. I’ve been experimenting on another thread here and the photos on the wall demonstrate a larger difference than hobbyists really want to believe. I bought stuff hoping I could mod it enough to make it work well. I probably could have come close, but when I got it in my hands and started looking at the effort required, it just wasn’t worth it for me.
I agree with others here, led color temp is a thing. I just don’t like it. Halogen still gets my vote. I have hid projectors in my truck and I believe the bulbs are listed as 3500k, though they look closer to 3100k, which was the indoor standard for television studio and theater lighting. That’s very natural, and especially with halogen, the CRI is wonderful. I believe CRI costs a few lumens to implement... so for led makers to “go there” in automotive applications, they (or then buying market” will have to vote with their wallets to choose a slightly less output led in exchange for the color quality.
