Since it came up…. have you noticed any change in Vf for those dedomed XM-L / XM-L2?
Lower output is what many of us care about the most. But lower output + higher Vf is an even worse situation. Just getting the same output at a higher Vf means a drop in efficiency… together that’s extra bad.
Didnt someone successfully even if accidentally dedome as a result of heating the LED via high amps? IIRC, they said the colour did not shift and I was wondering if maybe that might translate to maintaining lumens too?
Maybe the ‘solution’/gasolene is the reason for all/much of the loses and colour shifts rather than dedoming perse?
I have 2 of the V6 2D and 2 V6 2A on the way from Craig. Intend to use the 2D as is, try to de-dome the 2A. We’ll see. If the tint is good on the 2D I might put one in the new Nitecore HC90 that’s coming with em. We’ll see how that light fares with it’s stock emitter and what it may take to change it.
Well actually heating is how many dedome - not everyone uses gas. XP-G2's I don't believe color shift as much as XM-L2's, so maybe that's why? I dedome using gas and vinh uses heat - I know our de-domed TN31's are very close to the same lumens, and I know his will color tint shift same way. Lot of speculation has gone around, but only known measured lights I've seen #'s on, or seen and measured myself seem to indicate same results.
My apologies. Thanks for taking the time this afternoon, really appreciate it.
I’m thinking I’ll try some set-ups with the 2D and 2A, get some base output measurements and then maybe try a de-dome with the 2A and see what changes. If it’ll de-dome clean and not tint shift too much, I’ll try a triple in a 14500 sized light. A Buddy wants another chopped mini-mag, these would be a good candidate to ramp it up a bit. If it acts like an XM-L instead of XP-G then a BLF17DD should allow higher amperage to the triple for bigger outputs, right?
So what do y’all think? Would/should the XP-L in a triple be similar to a triple XM-L? I have a triple XM-L with de-domed emitters, wondering if it should be comparable.
An AW IMR14500 gives over 7A to this triple XM-L set-up through the BLF17DD.
I ordered two XP-L leds, can't even remember which of the tints. When they are in I can do a amp/voltage/output test up to 7A, and when I'm at it I might as well do a dedome (I do that hot) and test it again. And since my vacation money is in (which really is for vacation, but I feel rich now ), I might do a crash test on the other one.
I’ve got a V5 2A on 16mm Noctigons, one domed and one in the gas. Thinking of using a Convoy C8 and running each through the paces, BLF17DD with a Samsung 20R, find out just what they do.
When the XM-L changed to XM-L2 we saw some differences in the face of the die. Here we go again. There seem to be dots arranged in a spiral pattern on the face of the die. Odd.
The XP-L V5 2A on a 16mm Noctigon in a Convoy C8 with BLF17DD and running an Efest 35A at 4.21V fresh off the charger shows 5.71A for 1252 OTF lumens at start, 1145 OTF at 30 seconds. I haven’t measured Vf, just put one together to see how it looks and acts. The tint here is nice, almost pure white actually. The hot spot anyway, the aura around the hot spot drops in intensity and is warmer. I don’t have any XP-G sized centering rings, so it’s in a standard butterfly centering ring and fiddled with when screwing the bezel down until I got it centered.
The beam profile is perfectly acceptable, I’d be willing to keep this light as is.
I tested the XM-L2 T6 3C on Ryans pill before I put this one in and with the cell at 4.15V it drew 5.93A for 1490 lumens and 1394 at 30. So, even the standard T6 is making more lumens.
I’ll be back to collect my check after I get some more things done, the other emitter should be ready to come out of the gas directly.
I put the de-domed XP-L in a SupFire F9, very close to being the same as a C8. This one, with a fresh 35A at 4.21V pulls 5.78A for 1363 OTF at start, 1301 at 30 seconds.
Here’s a side by side photo of the hot spot. Camera got the white balance odd, the de-domed looks about right but the domed one shows much more blue in this pic than the eye sees. Go figure.
Thanks for the pictures. That die does look very familiar. So the story sofar is that indeed it seems like an xml2 die on a smaller substrate, leading to a somewhat worse heatpath and a bit lower output?