Tint, Binning, and CRI Explained (For XM-L LEDs)

Oops, didn't know they went down to sw27 in H1. Thanks.

many thanks, nice,…
are there flashlights available already in nichia 2700- 3000k warm?, and will these be at 200 lumens max?.

thanks.
what would be the best to do?.
a body and a p60 drop in?.

thanks.

Sorry, folks, but I’m going to throw a big monkey-wrench into the gearcase here…

I read and believed this “CRI” business, even though no one could detail it out well enough to make sense. I get that light reflects off colored objects and makes them “look” that way, and that different light colors reflect differently. K? (You should see my next-door neighbor’s mineral display with two “black lights” of different, user-selectable frequencies to make the rocks shine!)

Here’s where I get lost: everywhere I look, I see LEDs described as very specifically MONOchromatic, e.g. “5000k”, etc. I studied the Datasheets too, so feel free to start there. The reality is more “BI-chromatic”, but that may not matter. Everywhere I can find any spectral power graphs, “100 CRI Sunlight” does NOT have the spiky chromatic peaks of an LED or xFL. My “color reference standard” (poor as it is) is a standard 100W bare incandescent bulb. It’s not “sunlight”, and the fundamental color can be found in these LEDs I own, but there’s no question the incan makes a lot MORE colors look good, than any LED (that I own) can.

Full disclosure: I did my homework and decided to try “5000k” (aka “NW”) from two sources, hoping for decent color rendition. TURNS OUT: the only way I can “get happy” with colors is to turn on TWO torches and point them at the same thing. Hence my idea of multiple, different-CBin emitters…

Look at it this way: “5000k” reflects “best” off a certain color. “6000k” reflects “best” off a certain OTHER color. Likewise the other Chromaticity bins. Sunlight, containing waves and particles of all colors, seems to include all those “bins” on its way to a 100 CRI.

Some say the “NW” LEDs enhance the green leaves on trees. I can see that, but what about the other colors, which are better enhanced by the “CW” emitter?

Yes, I get that the answer is a multi-emitter host with all different Chromaticity bins!!! (I’d even accept the multiple different-colored shadows!!)

How is any of this helpful for single-source flashlight/torch users? Is there some way we (outside of “Manufacturer Support”) can expand the chromaticity peaks of an LED?? I would LOVE to know how to make the “dull 60W yellow-brown” of 5000k or lower (3000k??? You gotta be kidding!) render ALL the objects in my yard close to sunlight color-levels (dimmer, of course!! I want the good colors!)

On that note, IS IT POSSIBLE that someone (best would be the manufacturer) has posted beamshots comparing the different C-bins? As a proud new owner of two braces of “3C” XM-Ls, I would dearly love to know (without having to fork over even more hard-earned cash) what the real-world difference is between “3C” and “3B”, e.g. I’d really rather see them without reflectors, just the bare LEDs shining on a plain White (not “off-white”) wall…

Sorry to disturb the waters. Inquiring minds want to know: How do we make colors look good with a mostly-monochromatic source? Is “close enough” really close enough? I know Cree offers an LED which lets you blend multiple RGB colors, but that’s exactly what I said above, just with 4 emitters in one package. LSI did the electronics world tons of Good, maybe integration is the answer here too? My current answer: stop wasting so much time with it! Pester the manufacturers to improve their QC (like “stop with the purple and green colored rings, please”) before they pop out the next “much brighter/more efficient/better sex-life XYZ v2.0”; and if you want good color rendition any time soon, get an incan.

That’s what I think. But you know how I can be…

Dim

I almost bought some 4C from fasttech and read a bad review. Was it yours?…

“Review XML 4C: I was looking for XM-L led with 4C tint, but with no luck, i found it only here on fasttech, so i bought immediately 5 pieces, but its some cool tint, not 4C. I have some XP-G2 leds with 4C tint, and they are much warmer and have more yellow color. This XM-L is more blueish. I am dissapointed.”

Could this be Fasttech editing their reviews? I wish I had taken note of who posted it. Now the above review has been deleted and replaced with this one!:

“This XM-L 4C tint is far better than my XP-G2 4C LEDs i have, they are too much yellow-grennish.”

Hm, I don’t see any reviews at all

The 20mm version have one review…

I remember the the not so good that Flashpilot quoted … Not there anymore… Dont know why its gone…

Ah I see. The person who posted the review has “4” reviews posted buy I can only find 3. Maybe they initially had the bad review, contacted FT who maybe sent a wrong emitter, and got a replacement and wrote a new review (deleting the old one that can’t be found)?

All speculation…

Thanks Scaru! This is most useful. Your efforts are definately appreciated!

Dan.

I was comparing 2 lights on white ceiling last night, a Spark SL6 with a T5 (probably 3C) emitter, and an IOS T4 5B1 P60 drop in in a Solarforce P1 host. I noticed I could not really differentiate much difference in the tint between the two of them. So that made me try to understand a bit better what I’m seeing and why, so I’ve been reading various threads for the last few hours. If anything the more I learn the more confused I seem to get. Some of the questions I was trying to figure out:

-I assume I am getting more lumens from the T5 than the T4.
-Accordingly, I assume I get a higher CRI from the T4?
-So what puzzles me, why do the 3C and 5B1 tints look roughly similar to me, is it because the surface I was using did not have any bearing on CRI and the difference would be more apparent to me if I was outside looking at foliage and flowers?

When I look at some of the XM-L2 emitters currently on offer at IOS I see some T3 6A1 and T4 5D2, but no T5’s of any sort listed. I’ve been trying to figure out if I should wait for some XM-L2 T5’s to show up, or go with a T3 or T4?

This also has me wondering if it would be more sensible to use SMO reflectors for the T6 and T5 bins, and perhaps OP reflectors for the T4 and T3 bins?

There are several NW XM-L2s with T5 bin. Some can be found in the LED database.

Im not familiar with the Spark, but you assume its using 3C tint, but then you say its very similar to the T4 5B1. Assuming things does not make a comparison between two emitter that easy. 3C tints are mostly T6 bin (yes lower bin exist). If its a T5, then its higher chance the emitter is warmer than a 3C.. Again, im doing assumptions too. Which really does not get us anywhere.

IMO, there is a quite large difference between 3C and 5B1 emitters. Large difference to me might be subtle to others... It depends on how you see things and what you consider a large difference.

You should be getting slightly more lumens from a T5 than a T4 at similar current. But you will probably not be able to tell by eye, especially if the lights are not at the exact same current, using the same reflector, and are side by side.

You are getting higher CRI from the T4 emitter from intl-outdoor. T4 does not always give you higher CRI though, but in this case it does. We are looking at 75-CRI Typical (for the T5) vs 80 CRI Minimum for the T4. There is no such thing as a T5 with 80+ CRI.

Thanks a lot for clarify that. I also wonder if I made an error on assuming the tint for that T5 that is in the Spark, I should have done more homework before I posted it from memory as a ‘3C’, I’m thinking now I probably got it wrong.

In order to get a better overview of what my current options are for getting some XM-L2 emitters I placed some sources that I may use on the chart. The difference between the sources for what I looked at are:

- Fasttech: Alu Base

- IOS: Noctigon copper base

  • Simon: require lots of 5 bare emitters and flow solder to base of your choice

I case this may help anyone else thought I may as well place it here:

I noticed the 5B1 is available as T5 or T4. Does that meant you’d get the same tint but more output from the T5 bin?

Thanks for sharing your fantastic tint chart. I have made a few in the past. But many emitters XM-L2s have arrived since I last made one. Yours seem to give a good picture of what is out there! :)

Yes, you get the same tint and more output, but you dont get as good color rendering. The T4 5B1 from IOS is the more special 80 CRI minimum version. :)

Personally, id sacrifice on step of brightness in order to get better color rendering.

I have just noticed, I seem to now have a lot more drivers and emitters than I have hosts to put them in. As well I also seem to have a few XM-L emitters on aluminum base that I’m not as keen on now that I have run across these comments. So now my dilemma is what to do with all the XM-L emitters. I’m thinking of putting them into affordable hosts, but then you have to give people 18650 batteries and chargers as well. Perhaps the only way to go is grab a bunch of the $5.00 host from FT that takes the CR123 primary cells, put the XM-L emitters into them, and then give them away.

Ive had the same issue. My solution to your problem.


Why bother with getting rid of a bunch of decent emitters in a bunch of different lights, when you can get rid of a bunch of emitters in one or few lights. There are several benefits.

1. You might actually like your new multi-emitter monster :bigsmile:

2. Instead of having a bunch of outdated lights, you only have one, or a few.

3. When you have several thousand lumens, mostly in flood. You don't really care that much if you are loosing out on that extra 20% of output.

4. If you decide to sell it, lots of outdated emitters gone! :)

Some might ask, what to do with all the stock emitters from the multi-emitter lights. Well, they are only CW T6. They are great for testing, playing with, frying, doing various de-doming experiments, having in bench setups when testing new driver circuits. Everyone should always have 3 in series, 3 in parallel, + 1 XM-L ready for testing new drivers.. :) Suddenly 7 emitters got a purpose! :)

If you have a bunch of emitters you don't like, you could always do an emitter giveaway here on BLF. If you don't have a decent purpose for them, there is probably someone else who have.

Good ideas, I’ll probably end up using all of them. Is that an actual head or optic than can be readily obtained in that picture? Maybe I can make a porch light or something.

Its an actual head..

Fandyfire 9 XM-L

Got it, comes with the emitters already I see. When I go to the site it has a pop-up telling me about the group buy for 18650, they must know I clicked through from BLF I guess. Thanks.

Thanks for the write up scaru!! Great reading material, lots of good info in a really easy way to understand!!