The CREE "Angular-Tint-Shift" flaw syndrome..It's causing brain damage.

DBSAR · 2018-05-01T06:29:19.000Z

ToyKeeper:

Usually I hear it called the Cree Rainbow… and maukka has measured it extensively. It’s also the reason why people have been avoiding XP-G3 emitters, because the increased efficiency comes at the cost of a significantly worse rainbow effect.

I wouldn’t exactly say it’s causing brain damage though, or that people haven’t noticed. That might be overstating things a bit.

I exaggerated on the brain damage part.

Mr.Poppy · 2018-05-01T06:37:59.000Z

I had to reply.

THIS! is why i gifted out my BLF A6, and bought XP-G2 over previously bought XP-G3 which I can’t use
XP-L HI is OK i think.
Nichia on the other hand is just so nice, but not so powerful

Boaz · 2018-05-01T08:08:44.000Z

I don't think you can blame your damaged brain to Cree leds .
People who knew you before Cree ever started making leds will testify to the fact you may have filled one to many Coleman lanterns in your day . But take heart ...
.... creative and crazy are close cousins.

djozz · 2018-05-01T08:23:20.000Z

It appears to be difficult to get it right. Even Nichia has not really mastered it, the 144A has big tint shift problems caused (at least partly) by an uneven phosfor layer, giving an ‘egg-yolk’ problem in the beam. Egg-yolks also appear in some XP-L Hi beams, varying with individual leds, which is weird because you can not see looking at the led what is causing it.

The best beams I have seen in current leds are from the 219B, Luxeon V and LH351D. And with the trophy going to the E21A, a difficult led in use but when you got it working and centered: :heart_eyes:

desmondkun · 2018-05-01T09:18:39.000Z

lol I read all your post carefulky because of “brain damage” in your topic’s title.

KawiBoy1428 · 2018-05-01T09:34:26.000Z

That is why the only Cree LED’s I prefer are the XP-L HI and XHP35 HI, they seem to be the cleanest.

ma_tumba · 2018-05-01T10:55:16.000Z

While this is not obvious from your beam shots, nichia 219b are also horrible as far as the tint shift is concerned.

The new e21 series are much better although far from perfect.

Nichias 083b and new Optisolis are completely free of any tint shift

komeko · 2018-05-01T11:10:49.000Z

It annoys me too much and that is why I am trying to exchange the emitters for the HI series. HP-L HI and XHP35 HI are clean. It is a pity that there is no XHP70.2 in the HI version.

nottawhackjob · 2018-05-01T13:32:47.000Z

Has anyone tried camera-type lens filters to see if a noticeable improvement can be detected?

Just wondering if it would be possible to correct these tint aberrations without affecting the original characteristics of the beam such as throw, spill, etc.

I’m also implying as well/tangentially that if AR glass is used is there any noticeable change to these tint aberrations vs a bare dome?

The_Driver1 · 2018-05-01T13:35:49.000Z

nottawhackjob:

Has anyone tried camera-type lens filters to see if a noticeable improvement can be detected?

Just wondering if it would be possible to correct these tint aberrations without affecting the original characteristics of the beam such as throw, spill, etc.

I’m also implying as well/tangentially that if AR glass is used is there any noticeable change to these tint aberrations vs a bare dome?

A filter glass would always alter all the parts of the beam, so also the good parts.

maukka · 2018-05-01T13:51:42.000Z

You could put a round filter (and a diffuser if necessary) on the center of the lens to only correct the spill/corona. Adjust size to fine tune.

Also totally not worth it, when you can just swap the emitter.

ma_tumba · 2018-05-01T14:17:39.000Z

This is what I did. Problem solved but maukka is quite right. Just too much trouble.link

maukka · 2018-05-01T14:20:12.000Z

That modification of the hotspot+corona with a ring that sits under the bezel is certainly easier to install. Good thinking.

ma_tumba · 2018-05-01T14:31:45.000Z

And this is my new grail. A mule with a zero tint shift. Just beautiful pure sunlight (kudos to Clemence, Tana, djozz) link

DBSAR · 2018-05-01T16:10:55.000Z

djozz:

It appears to be difficult to get it right. Even Nichia has not really mastered it, the 144A has big tint shift problems caused (at least partly) by an uneven phosfor layer, giving an ‘egg-yolk’ problem in the beam. Egg-yolks also appear in some XP-L Hi beams, varying with individual leds, which is weird because you can not see looking at the led what is causing it.

The best beams I have seen in current leds are from the 219B, Luxeon V and LH351D. And with the trophy going to the E21A, a difficult led in use but when you got it working and centered: :heart_eyes:

I forgot to mention that most higher grade SMD LEDs don’t have the angular tint shift issue, (probably because of the flat embedded die design of them, but they don’t make good LEDs for reflectors is a drawback.

DBSAR · 2018-05-01T16:12:33.000Z

KawiBoy1428:

That is why the only Cree LED’s I prefer are the XP-L HI and XHP35 HI, they seem to be the cleanest.

Same here, I have swapped in many XP-L HI emitters in lights i use.

gchart · 2018-05-01T16:13:42.000Z

I have really liked the LH351D’s lately. Swapped those into some of my recent lights… very nice beam.

DBSAR · 2018-05-01T16:28:38.000Z

gchart:

I have really liked the LH351D’s lately. Swapped those into some of my recent lights… very nice beam.

I hope to check those out soon. ( have not tried any yet.

stephenk · 2018-05-01T21:17:51.000Z

At the end of the day, if the tint shift is not an issue for Cree’s main market (which is not flashlights), then I doubt they’ll change.

Ronin42 · 2018-05-01T21:59:30.000Z

+1

Have always liked the MT-G2

I think we all should boycott all Cree Leds (except for the MT-G2) (That will send our message!!!)

Or will they even notice?