The Yellow Q8 (added a test of a pink Epileds 5050 led in post#18)

Flashlight Modding and DIY Parts
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I have a couple of these high power Epileds 5050 colour leds from aliexpress in house for six months now but never came round to using them. I did an output test on a red one (I posted it somewhere I think) and a pink one (not posted yet but it was a lot of pink!), and now I found time for a test, and mod, of the Golden Yellow version. It is sold as a colour led and not sold as a low colour temperature white led, but they do state a colour temperature of 2000K. And it is clear from the appearance that we have here a phosfor-converted blue led so the width of the spectrum peak could be wide enough to actually show some CRI.

At least the output is solid, as expected from a converted blue 5050 led. Method as always, see for details my earlier white led tests.

It is a very usable led actually. A nice low Vf (lower than an XM-L2) good output, and the led lasted up to 9A. It died at 9.5A with some epic damage, not even the bond wires burned but a whole section under the phosfor went black:

I had a Q8 that was in between leds, it was converted to a lantern but I think the BLF lantern will become much better so I built it back to a flashlight and put four of these yellow fellows in there for the time being (I hope for high CRI SST-40 leds to come out at some point). To fit the 5050 leds I used a led4power Q8 board with the 5050 pads, made a clamp for it because the board-screws could not be used with this board, I reamed the 4 reflector holes from 6.2mm to 6.7mm so it can fit a standard XM butterflyshape centerpieces, and I used a Kaidomain 55mm coated lens.

Although the springs on this Q8 were not bypassed and the led wires were kept long and just 20AWG, I first expected that the current would be too high on high-drain cells, but after some trying out I got 14.3 A on fully loaded VTC6 cells, which is quite perfect for these leds, they run at 81% from max.

The output that I measured is 3500 lumen at start, 3300 lumen at 30 seconds. A lot of yellow that is! 8^)

From the balcony it makes the complete square looking yellow. First shot is control, next the Yellow Q8 at max. The big trees are at 25 meter but I can see the end of the square at 100 meter turn yellow as well when aiming the hotspot.

When measuring the tint of the hotspot (the brightness does not matter much, even the spill measures the same as the hotspot) it even has an acceptable CRI of 64, with a CCT far above the BBL.

That was fun, thanks for reading :slight_smile:

Edit Jan20: I added a test of a pink Epileds 5050 led in post #18.

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Cool :slight_smile: :+1:

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Fresh snowfall here, bet it would look cool at night on it.

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Really looking forward to your test results on the pink one when you get a chance sir.

I almost bought some big pink COB’s last month but didn’t want to deal with the inefficiencies of Chinese COB’s, I didn’t know pink epileds existed.

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I wanted to do a mod with the pink led first, to post with the led-test, but I may skip that and just post the test one of these days (but not now because I’m off to bed in a moment).

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Interesting choice of LEDs. Seems like it would be fun to play with.

Do you think the spectrum is different from what other manufacturers market as phosphor- converted amber?

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PC-amber is very similar but a bit more orange. I just measured a PC-amber flashlight (with a ProLight PC-amber led) and the peak in the spectrum is just a bit more towards red, colour temp is 1900K. The CCT btw is, just as the yellow one, way above the BBL. Left the yellow hotspot, right the PC-amber hotspot:

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Actually, quite warm :stuck_out_tongue:

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Don’t eat the yellow snow

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Thanks for the testing djozz. Are you leaving these leds in the Q8 long term?

Yellow snow, you can have it. :open_mouth:

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:stuck_out_tongue:

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Ewww, didn’t think of that.

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Wow. I”m envious, as I have made a lot of amber lights to avoid screwing up my nighttime sleep cycle.

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Maybe 3300 lumen of yellow is not ideal for your sleep cycle.

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It probably depends on Luminus. I think it makes sense that now that they started with the other cool and neutral 70CRI CCT’s of the SST-40, but not 4000K and warmer, that at some point they finish the SST-40 line-up with warm 95CRI versions. One can hope, right?

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Whats up with the Giant Gangster Whitewalls on the chick bike, Is that a happening fad over there for cyclists or a safety thing? The Yellow Bile colored beam really makes them POP! :smiley: :+1:

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It is very common to have a reflective strip on the tire over here, it helps a lot with safety. But this particular bike seems to have reflective rims instead.
Same bike in daytime:

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There you go ^
It would make sense if the behaviour was similar to the yellow one but it seems a quite different led. It did not even die at 10A when I stopped the test.
I made an S2+ shorty with BLF-A6 driver to check the led. It is indeed very pink and puts out 400 lumen on a 18350 battery. With some bypasses and such it should do over 600 lumen.

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respect you got the rosiest tine ever achieved in a flashlight

Kawiboy his camarea has no or not good image stablisation