What is an acceptable tint/ beam color difference?

I recently bought a nitecore p12gt and I am very impressed with the power and throw of the beam, however there is an off color(yellow or green maybe?) circle right in the middle that continues to bug me. I have had a zebralight sc5w op for edc that is very uniform throughout the beam, are these just higher quality lights? Basically, I am trying to figure out if I am being to picky or if I should be thinking about returning the light for replacement/repair.

welcome to the forum

I think the path of least stress is to return it. Alternatively, you can exchange and hope the next one is different, but, I dont think it will be.

If you use the light for long distances outdoors and the center tint is going to bother you there too, because you now know its there, I think it is perfectly reasonable for you to return it.

while you are looking for what to buy instead, you may find this photo, it is a link too, interesting


I post it because you mentioned the green center.. and Im always telling people how important the CRI of a light is, to me, and why I think they should try a Nichia LED

many people tolerate green tint to get maximum brightness, depends on personal needs and priorities. Nichia LEDs are less bright and also more colorful, that is, they show fleshtones better, and things that have reds in them.. but I digress, as usual

enjoy the journey

Some of my cool white lights have a slight yellowish-greenish color in the corona (the area just outside the hotspot). They aren't as bad as the picture above of the S2+ and I only notice on a white wall and specifically when the distance between light and wall is less than 4 feet. Outside you can't tell. I've seen it on a number of lights and assume that its the nature of many LEDs. As long as its not as bad as the example above, I just live with it.

Jon, thank you for helping me think I'm not crazy about this, but I havnt ever really had this kind of issue before with a light. I have read about it and have seen some bad ones in pictures, such as the one you posted, but had not personally had any lights exhibit this. It is nowhere near as bad as that example though. I just emailed nitecore to inquire about their return/warranty process and got an automated response saying:
"[FONT=tahoma, sans-serif]We're going to have a Chinese New Year Holiday from January 26th, 2017 to February 2nd, 2017, we'll back on February 3rd, 2017, [/FONT]your query will be dealt with as soon as possible."

Thats a new one for me! Amazing how small our world has become with internet around!

Buying lights that use LED's with lower ME(MacAdam Ellipse) numbers will greatly minimize the colour variation(tint lottery). As will buying a light that has a neutral emitter as apposed to cool or warm. Unfortunately, very few mainstream light manufactures offer lights with low ME neutral emitters. You can have many/most lights modded with these emitters however.

It isn't always caused by the LED alone either. It can be caused by, or exaggerated by, the AR(anti-reflective) coatings on the lens or by the reflector design as well. Some companies are starting to use low colour distortion AR coatings to help minimize these effects.

Certain LED's are notorious for high tint shift(colour change from hotspot to corona to spill) as well. The Cree XM-L2 is somewhat notorious for this. You can minimize this effect by diffusing your XM-L2 powered light or buying one with built in diffusion(frosted lens). Strongly orange peeled reflectors can help as well. Many other LED's have much less tint shift. Most Nichia and Luxeon LED's have less tint shift for instance but, they generally have a significant lumen penalty compared to Cree's and often an efficiency/runtime penalty as well.

Chasing the perfect colour temp and tint can be hard and expensive sometimes. And, one thing to keep in mind is that under normal flashlight usage(not white wall hunting) a bit of colour or tint shift in a beam isn't even noticed unless you really try to look for it or it is really bad. Plus, the human eye will automatically adjust and filter out what little colour you first see as well. The vast majority of flashlight users don't even notice these kind of things and just use their lights but, we are enthusiasts and tend to obsess and notice the little things.

I hope this helps and good luck with your search for the perfect light:thumbsup:

Tachead, the sc5w op has the xm-L2 if I am not mistaken and it seems to have great uniform color throughout the entire hotspot, and peripheral. It does have an orange peel style reflector, so possibly that helps to distribute imperfections better? The p12gt comes with the Cree XP-L HI V3, I don't really know much about the different led's, I will have to do a little more research on it, since you said that some leds are more likely than others to show this problem. I did not realize until I started looking into the color on this light that this was such prevalent thing with led's. I will try to get a picture up to show what I have going on.

Hammbone said:

Tachead, the sc5w op has the xm-L2 if I am not mistaken and it seems to have great uniform color throughout the entire hotspot, and peripheral. It does have an orange peel style reflector, so possibly that helps to distribute imperfections better? The p12gt comes with the Cree XP-L HI V3, I don't really know much about the different led's, I will have to do a little more research on it, since you said that some leds are more likely than others to show this problem. I did not realize until I started looking into the color on this light that this was such prevalent thing with led's. I will try to get a picture up to show what I have going on.

Click to expand...

Yes, OP reflectors can help. Reflector geometry and anti-reflective coating choice can help as well. Keep in mind though, it is some what of a lottery as well. Emitters are organized into what they call "bins" and there is a certain variation or range within each bin. This variation increases as the MacAdam Ellipse number goes up. And, unfortunately many light manufacturers don't even specify what bin the emitters they are using are from. It can be frustrating sometimes, the tint lottery. If I were you, I would exchange the light and see if you get a better sample if you can. You may have just gotten a sample with a strong green colour but, they might not all be like that.

Here is a picture of what I am seeing. It is more of a bullseye spot right in the middle.

IMG][/IMG]

It is noticable on all brightness levels and at pretty much all distances. Is this a big enough flaw to play the lottery for or is this on the low end and I would be best to deal with it rather than risk getting one worse than this?

My new TN12 has some green in the center of the hotspot as well as just outside the hotspot. The XP-L emitter in mine is apparently notorious for this? For me the question is not whether to exchange it for another one, but rather whether I should return it and buy an altogether different light.

In my case my light is otherwise exactly what I want at an unbeatable price. Considering that I don't notice the problem much outside means the light is suitable for my purposes and I'll keep it. I just have to try snowshoeing with it, to see how it looks there, as I do that regularly.

Hammbone, I haven't seen a light with a beam pattern like that. I'd try to exchange it knowing that if it bothers you now its always going to bother you. Most of the time its just a single light with an anomoly and you just got unlucky with the tint lottery. However I have seen tint problems almost across the board on specific models.......(ie: the Thrunite TH20 headlamp). I purchased a Fenix HL25 headlamp from the Fenix-store insider sales because its being obsoleted and it was a good price and I got a greenish tinted XP-G2. So I called customer support to see if they had seen that on that particular model and he said he hadn't heard about anything. So I purchased another........and it also had a greenish tint. So I gave up on that model and gave the best one to my son and I replaced the LED on the other because I then became suspicious that all those HL-25's were that way.

What we need to hear from are some other P12GT owners.

You're not the only one. My P12gt had the same problem. I actually returned it to Amazon because it bugged me enough. It was very noticeable on all modes. I did a search a month ago, and there has been other people with the p12gt who have the same issue.

I would return that one personally. However, it seems to be common in that model. I would get another model all together as that would bug me. People were talking about a greenish tint in the corona of the Surefire PX2 Fury Tactical. I have a PX2 Fury Tactical model and compared to my PX3 Fury Tactical model, I noticed a very slight green color, and may not have noticed it if not for reading about it. So what I did was take both of the lights into the bathroom where my girlfriend was taking her normal two hours to get ready to go out, Lol, and asked her what color she saw while shining them both on the white wall at the same time, I never told her anything about any flashlight having a greenish tint. After a few seconds she said, "green". I said, "crap". Then she told me that it went away after a few seconds though. I looked at what she was saying and it seemed to be true. I don't know if our eyes just got used to it after a few seconds or what, but if not directly compared to another light it is pretty hard to see on a white wall, and when used outside it is not noticeable so I live with it. I don't think I would want to keep that one though.

Well, It looks like the consensus is it is not acceptable, and I will be returning it. Glad I asked because I only had a couple more days before the return period is up. I will say though, I am disappointed to hear that this may be a common issue with this light though because I really liked the feel of it and it's throw compared to its size and the fact that it fit my rifle very nicely. Guess I will be looking for a new 18650 light to use all these new cells. Suggestions?

jon_slider said:

welcome to the forum

I think the path of least stress is to return it. Alternatively, you can exchange and hope the next one is different, but, I dont think it will be.

If you use the light for long distances outdoors and the center tint is going to bother you there too, because you now know its there, I think it is perfectly reasonable for you to return it.

while you are looking for what to buy instead, you may find this photo, it is a link too, interesting


I post it because you mentioned the green center.. and Im always telling people how important the CRI of a light is, to me, and why I think they should try a Nichia LED

many people tolerate green tint to get maximum brightness, depends on personal needs and priorities. Nichia LEDs are less bright and also more colorful, that is, they show fleshtones better, and things that have reds in them.. but I digress, as usual

enjoy the journey

Click to expand...

I hear you about Nichia LEDs. But the same problem exists in that led too. I have Lumintop IYP365 Nichia 219b with a distinct yellow spot in the middle of the beam.

However I got it extremely cheap (10usd) and I like it enough to take my chances and buy another one.

Hammbone said:

Well, It looks like the consensus is it is not acceptable, and I will be returning it. Glad I asked because I only had a couple more days before the return period is up. I will say though, I am disappointed to hear that this may be a common issue with this light though because I really liked the feel of it and it's throw compared to its size and the fact that it fit my rifle very nicely. Guess I will be looking for a new 18650 light to use all these new cells. Suggestions?

Click to expand...

You could try the Fenix PD32 2016 model with XP-L HI LED. It's pretty much the same kind of light, has springs on both ends so you can use protected or flat top batteries. Lowest mode won't be as low but the top ends are pretty much the same. Throw may not be as far but neither of those lights would be classified as a throwers anyhow. Tail switch on the PD32 is a little stiffer. Both lights have pros and cons compared to each other. My preference is to the PD32 but to others it will be the other way around. My favorite Nitecore light with 18650 capability is the MT20C because I just love that up/dn mode select button and prefer tactical tail switches. For the life of me I can't figure why Nitecore would only put an XP-G2 in it though. But look at the PD32, 2016 model.