XM-L T5

Nice GIF, I'm glad I got the larger reflector of the C8, even though several of those XM-L lights have literally the exact same beam shot images on KD. :/ The A20 is not quite big enough even for a flooder, but DANG can it flood. :D Awesome.

Cutter has 14mm boards ...

Posted a link [ first post ] for full sized pictures if anyone wants them ... Will try for a slower gif

http://www.makeagif.com/xrvpJ2

Here it is slower

Actually the little light is so bright [ spill is brighter ] it makes it look like it has more flood .. [ I guess it has brighter flood ]

+ the flood is so bright , it makes the center look darker [ optical illusion ] , I guess the camera cant see what the human eye can ...

Thats why I posted a link for the larger images if anyone wants them ..

Unfortunately I dont have a digital SLR with timed exposure , so the pictures do LIE a little ...

But the little XM-L T5 is hot stuff .. Just cant wait for the T6's and hopefully drive them much harder ..

I might buy another T5 , the tint is just perfect for me [ and see how hard it can go in a P60 host ]

XML rules !

But just to say , to the naked eye , it was just awesome , so much light from a EDC , its a sight to behold ...

I have a A20B on the mail. I were planning to use it as is but I can transplant its R2 to a thrower and an XM-L or XR-G into A20B. How does it mod? It requires 14mm emitters at most I belive, am I right?

I don't have a 14mm XM-L right now but a 12.8mm R5 is also on the mail. I wonder which one would be most efficient at something like 1.2A current to LED.

14mm would probably be the go ..

XM-L is the most efficient , then Xp-G ...

First thing to watch for = Is the emitter glued down ? Might make it hard to remove without destroying it ...

Then you need to glue the XM-L in place [ thermal epoxy ]

Do you need a new driver ??? or do you wish to use the original ..

Soldering ?

Checking for shorts [ XP-G / XM-L design lends itself to shorting , especially with reflectors that press down ]

Moding is a learning experience , be prepared to break stuff ...

I'll better reserve XP-G leds to 2xAA lights as boost should work better with a lower Vf. I guess any 18650 light can unleash the potential of an XM-L. I plan to start with something with more space, like an UltraFire C8 or a bigger TR-1200 body. Ordered my insulators, thermal epoxy, 2.8 linear and 3A buck drivers, empty P60 drop-ins, Dremel tools and so on... :)

I did see somewhere on CPF that an XP-G R5 was brighter than an (unstated bin, probably T5) XM-L until you went past 1500mA. But my memory may be at fault. The XM-L is more efficient at any given current, but not necessarily brighter. It is when the XM-L becomes much less efficient that it gets really bright. The same is true for most LEDs

I don't think that's true about the output. Cree determines the bins at 350mA. So a higher bin will always be more efficient and put out more total lumens at pretty much any current than a lower bin. Now the brightness of the LED die itself (and therefore the throw) may not increase for the XM-L until you get past what the XP-G is rated for which is 1500mA. That's more of a lumens/mm2 thing though.

That is not quite true. XM-L's are binned @ 700mA

I went looking for the post at the Other Place and gave up as they've rearranged it in a way I do not find useful. I gave up on searching as a bunch of patients needed seeing. Wonder how many threads "got lost" this time?

I've no idea why but a lot of websites I look at daily have been redesigned in the last few weeks.

Nearly all of them are now worse - except here. Personally I'd prefer slightly smaller text but given that a pinching gesture on the mouse will fix this, it really isn't a problem

Yeah, you're right. That seems inconsistent on Cree's part. So really the XM-L T6 has about the same output at 1500mA as an XP-G S4 would. And the XM-L T5 is about equal to an XP-G S3.

Very informative thread. Thanks!

This ought to make things very interesting once supplies catch up with the inital demand and economies of scale begin to kick in.

Where do the XP-G S3/S4 start to lose efficiency though? The XP-G R5 levels out really fast around 1 amp in the tests I've seen. Nowhere near linear between 1 and 1.5 amps. Did you make that consideration part of your calculation? And where are those test numbers for the S3/S4?

From KD's XM-L T6 drop in, Don was getting:
436 Lumens @ 3.736V battery / 1523mA tail

An XP-G S4 will do that?

You really can't say this as you really can't compare the bins on these two LEDs comfortably. First, as uncajesse pointed out direct multiplication doesn't take in to account decreasing output and losses to heat. It's likely that the XM-L is geared towards accepting a MUCH higher current than the XP-G due to the larger die.

Secondly, S3 bins of Cree emitters are extremely rare in the wild and S4's are pretty well unheard of right now, while XM-L T5s and T6s are shipping. Heck, 4Sevens is claiming that large numbers of S2 bins are hard to get.

Cree has graphs of output vs. current in the product sheets for each LED. I'm using information at the wiki:

http://flashlight-wiki.com/Cree

which in turn is based on a table that Isotco (is that someone here?) posted at DX, which in turn is based on the Cree literature. So the nominal output of the LED is given for 350mA, which in the graph is 100%. Then you can get values for 700mA and 1000mA by figuring out the factor to multiply by. I got the graph below from the Cree datasheet (in black) and added lines: the blue (350mA), green (750mA700mA), and purple (1000mA) lines plus a straight red line to show how the efficiency is tailing off. Anyway, increase the 350mA value (for R5 Cree says 139-148 lumens) to 185% for 700mA and 250% for 1000mA. At 1500mA it looks to be about 330%. This graph is for 25 degrees C, so it doesn't take into account that you would have a lot of heat at higher currents that you need to get rid of in a hurry to maintain that temperature.Anyway, as long as the tables at the Wiki have the current values you want, you don't have to mess with the graphs, and the XM-L and XP-G both have values shown for 1500mA, so I compared those. And the lumens at 1500mA match up with bins as I said. The S4 doesn't exist, but I think the 350mA values have been extrapolated from the Cree binning guide which go all the way up to S3.

I think you mean 700 mA instead of 750 mA. The same 'mistake' can be found in the Wiki in the Cree article, 2 lines into the XM-L section. In the sceme/diagram the 700 mA is correctly used.

Well, at least I'm consistent . . . I fixed that. Thanks for signing up. I went ahead and confirmed you so you can fix any more mistakes you find on your own!

Thank you for your confidence, I have thoughts of contributing with an article, perhaps concerning tint. I have a little knowledge as I worked professionally on a 'true color' camera and also possesses a color analyzer that I use for tint measurements.

By the way, I am offering my assistance in measuring tint of emitters for other members if they pay the postage fee. When I buy emitters I wil report the tint in the 'Tint Measurements' thread.

When the manufacturer orders emitters from Cree, the narrowest range of eg. cool white XP-G R5 that can be ordered covers 5300K thru 7000K (called kit no.00H50).

If the manufacturers wishes a narrower range they have to sort the emitters. I don't think they do that for budget lights. Therefore tint is normally a draw of luck.

Where did you get that A20 with no strobes?

Anyone found XMLs in 14mm star in DX, KD or so?