The coolest option (XP-L Hi 1A) and coolest running battery, it’s comfortable on stock settings. Can’t wait for someone else to test this combo to back my result up.
This seems pretty low?
It’s supposed to be over 2K even on a depleted 18350 stock?
PS: i guess you intentionally limited the output? Sorry if i missed something.
Colour leds do not have the output that white leds have, and XP-E2’s only have a small die. Just over 250 lumen per led sounds like close to max.
Crikey 3,800 lumens with Keeppower 18350 750mah but quickly down to 3,200.
Right, what Jos said. The XP-E2 green has about a 1.9A MAX. The die is TINY. Getting 1031 lumens from a quad of em is pretty dang good, I thought. Lot of green light. Interesting to see the green tint change while ramping through the power spectrum, below the 7135 chip it’s a deeper richer green, above it it’s yellow and into the blue’s a bit. Still a nice green, but the way it changes on the dual channel output is pretty cool.
Cyan leds show even more colour shift with changing current.
To get more output from a colour led, several manufacturers make colours by converting a blue led to different colours with a phosfor layer (phosfor converted colour leds), like white leds but with different phosfors. They do have a wider spectral emission band than direct colour leds. I measured a lime Rebel at over 1000 lumen a few years ago, with 750 lumen OTF of a C8. Four of those on DTP boards would make a nice D4 too 
That is a whole lotta green light.
It’s really interesting that the tint changes so much at different power levels. I’ll have to remember that and not overdrive color LEDs…
At the moment I’m just doing 1A per die, with four dies total. That’s the rated maximum for these XQ-E emitters though. If you thought XP-E2 was small, you should try XQ-E. According to Cree, “The new, game-changing LED packs the lighting-class performance of the XP-E2 into a package that is 78 percent smaller.” And they make a factory de-domed version too.
Hmmm. Someone needs to make a liquid crystal band that changes color with temperature, as a warning device.
That sounds a bit high, even for the “BLF lumen” unit commonly used around here. If you get numbers higher than DB Custom, you might want to recalibrate your light box. He usually has things maxed out about as far as they can go.
It’s not easy to calibrate to ANSI lumens, so people mostly calibrate to an average of several trusted lights based on the lights’ specs. Which gets us the “selfbuilt lumen” or “ZebraLight lumen” or “BLF lumen” or similar… which appears to be different than an ANSI lumen.
I calibrated mine to match selfbuilt’s numbers, which also happens to closely match the numbers from ZebraLight and most of the reviewers on BLF… even though the true ANSI numbers are probably lower. But even so, 5,330 from an unmodded D4 sounds too high. That’s 23% higher than expected.
Compared to a 2,400 lumen DQG Tiny 22650:
Emisar D4 XP-L 6500K
Sony VTC5A - 5,490 lumens
Samsung 30Q - 5,200 lumens
Sony VTC6 - 4,670 lumens
Keeppower 750mah - 3,800 lumens
Manker E14 II
3,470 lumens
Olight H2R
2,540 lumens
If the XP-L 5000k can hit 4,300 with a VCT6? I dare say the 6500k with VTC5A can add plenty more.
I’m working out my readings compared to my 2 DQG’s at immediate turn on. The DQG’s have a discrepancy of circa 100 lumens.
It’s amazing how much Vinh’s lighs get from the VTC5A. I think he was claiming about 3,000 lumens more on his X45vn.
This doesn’t really help with the D4 as it is now, but I have a totally new firmware working which lets you set the lowest and highest levels in case you want to limit the output to a specific range. For example, if moon is too low, you can make it start at a higher level. Or if turbo is too hot, you can set the highest ramp level to something more reasonable. True turbo is still accessible though — turn the light on, then double-click.
I’m not sure what the best approach is there. Should a double-click from off go to the user-configured ceiling or should it go to the true maximum? At the moment, it goes to the user-configured value, and then a second double-click is required to reach the true turbo. Unless the user configures the ramp to use the true maximum, of course, in which case it’s a non-issue.
I got 4322 lm with XP-L HI 6500K and a brand new Efest purple 3000mAh cell. Looking at HKJ’s measurements, it appears identical to a Samsung 30Q.
From what I’ve seen, the VTC5A gives an extra burst at full charge. For the first 200mAh or so, it can do 20A at the same voltage levels that a 30Q gets at 15A… and then it starts to drop. Based on HKJ’s graphs, the VTC5A should be able to run brighter than a 30Q or Efest for the first 3 minutes or so (first 1000 mAh), assuming the light is water-cooled to avoid thermal regulation. After that, the 30Q should be brighter, and lasts longer.
Maybe it can get significantly more lumens on a fresh VTC5A, but 5,490 still sounds a bit high. The other numbers look high too:
- Keeppower 18350 cell = 3,800 lm? Expected amount: ~3,200.
- 30Q cell = 5,200 lm? I measured 4,322 with the same configuration.
So, the numbers look about 18% to 20% too high. If I scale down the VTC5A’s 5,490 lm measurement down by the same amount, it’s only 4,600 lm… which sounds about right.
Maukka just this week carefully measured the output of a flashlight for me that I sent him, with his new well calibrated sphere. That measurement would make my ‘djozz-lumen’ 7% too high (about what I expected from earlier less careful measurements on flashlights that had been measured before in Germany), and the djozz-lumen is already a pretty low one for BLF-standards.
We can look back to the amperage at the tail, on my test of the Sanyo 20700A it pulled over 25A.
No matter now, if I put that cell back on the light with these green emitters I’d have magic smoke in a heartbeat! lol
(Not even possible, I reglued the driver in, replaced the spring on the driver, removed the spacers on the tail spring pcb, can’t go back, not easily.)
Didn’t realize that was 1k lumens of GREEN light! That’s a lot of green indeed! :person_facepalming:
I’m curious how low the CRI gets?
Speaking of low CRI… are there NW ultra low CRI leds that would make everything look like in a black and white picture? I guess it just doesn’t make sense.
No matter which light I compare it against it is reading over twice as high as lights that are genuinely accepted as 2400-2600 lumen lights, the DQG 22650, Olight H2R and Acebeam EC50 Gen II for example. MY D4 reading isn’t far off my M43 Nichia.
D4 can only hold these 5k outputs for a split second though. Obviously 5 seconds in a 1000 lumens have been lost.
Did another runtime test starting at 1000lm & handheld just for curiosity, maintains around 550 - 650 for half an hour on aspire 18350
I just put XP-L HI V3 3C in the D4. Fresh VTC6 it’s pulling 17.8A. It significantly brighter than the 219c. Thinking about putting in 219C D320 into my other D4.
CRI can actually go below zero. Low-pressure sodium vapor lights are so bad at color that their CRI is negative.