Floody reflector accentuating the greenish corona for overall average greenish tint?

hiuintahs

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I recently replaced the LED on my Fenix HL25 headlamp because the original was too green for me. I went with an XP-G2, 5700K and it also was too green. When I had that LED on a star on my metal work bench reflecting off of the ceiling with another reflector, you could see the hot spot as very white and the corona around it kind of greenish. I think its kind of normal to have a greenish corona with a more white hotspot, but I don't know why.

When I put this LED into the HL25, I'm assuming its the floody nature of the reflector that averages in the greenish corona into the overall beam. When I went to an XP-G2 6000k, the green diminished greatly. Now I'm thinking that if I want to eliminate green, I have to go with more cool white or I have to go to 5000k or lower.

I also had an XP-L, V3, 5700k LED and so I put that in the HL25 and also have a slight greenish tint. But that same LED with a different reflector exhibited a very white hot spot and slightly greenish corona. So for the time being, I'm steering away from 5700k LEDs when used with floody reflectors. I'm thinking that range of color temperature may come with more greenish corona. This is something new to me and wondering if others have seen this.

By the way that XP-L, V3 gave me nearly 20% increase in output over the XP-G2, R5 and the beam profile remains the same (or at least I couldn't tell the difference).
 

Zak

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What were the tint bins of these emitters? Cree's B and C bins are on the green side of the blackbody line, while A and D are on the red side, but usually not very far to the red side. I've only seen one distinctly rosy Cree emitter, a 4000K XHP35 of unknown tint bin in an Armytek Prime.

Nichia 219Bs and 219Cs come in 5700K. The 219B in particular is unlikely to be green; Kaidomain stocks them in 5700K. Nichias tend to have less tint shift across the beam than Crees.
 

hiuintahs

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Thanks Zak for the reply. I haven't been following this thread and thought I'd just check to see if any responses...........a month has gone by. "tint shift across the beam". That is a good definition of what I am seeing.

I'm periodically having to place an order at Digikey or Mouser for work and will at times throw an LED in there so as to take advantage of not having to pay for shipping. Those guys don't post the bin # of the LEDs, just the P/N. I once asked Mouser customer service to check the bin and suggested they post that too. He found the bin# on that reel of the particular LED I was interested in and mentioned it to me, but they have never taken that advice to heart. So I have no idea what the color bins are when buying from those guys. I purchase Bergquist blank star MCPCB boards to which I can flow an LED onto so as to check it out before installing in a flashlight.

So I purchased a variety of XP-L LEDs: 4500K, 5000K, 5700K, 6200K to see what I liked. The 5000K and the 5700K were as a whole as you would expect: the 5000K more NW than the 5700k. But with a reflector on them where the hotspot and corona are defined on a wall, the corona exhibited too much greenish tint whereas the hotspot was white with its respective color temperature. I put the 4500k LED in a Nitecore MT20C (came stock with XP-G2) and I liked it other than its a bit too yellow with some greenish offset for me. But I'm living with it for the time being.

I got lucky with an XM-L2, U2 5000K LED that I bought and placed that one in a Sunwayman V20A. I like that color a lot and the corona and hotspot are pretty much the same color. Maybe its the nature of the XM-L2 vs those Xp-G2 / XP-L LEDs.......I don't know........... but with the ones I was buying, the reflectors of the lights I was trying to put them into averaged out the corona tint with the hotspot tint to make for overall too greenish tint for me. But I did like this particular XM-L2 5000k LED I bought, so I purchased another one for my SWM V11R. Hopefully it will be the same color as the previous one.

Maybe I need to inquire of customer service to find out what the color bin of these LEDs I've bought actually are. The last customer service rep I dealt with was very willing to help.........it's just that he was having a hard time with the concept that the actual part number didn't provide enough information such as the color binning.
 
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kosPap

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does the green tint get greener in the low modes?

there is another scenario.
If a light is conctant current driven (and not PWM driven) the LEDs (any LED) will show its tint on low drive current.
 
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