The tests you posted are not directly comparable due to different bins, tints and sources. Although even then if you factor in the Cree binning margin for error into the mix, it is still around 5% for those tests. Don’t forget that each bin can vary by as much as 14%.
I have tested the “same” LED’s on my own sphere purchased at different times from different places and got wildly different results.
Cree builds in a 14% margin for error into each LED bin. So each LED can vary as much as 14% and still be binned the same.
The highest single XP-L HI I have seen reported is around 1400-1500 lumens by many different people. With the new V3 there might be one a bit above 1500 now days. Yet those numbers say that we should be seeing almost 1800 lumens @ 6A with a U5.
Sorry, that just won’t happen in the real world, If it would why does the Astrolux S2 only make about 1300 lumens @ ~6A with a V2 emitter? Interestingly, that is exactly what my test says it should make with reflector and lens losses….
Now don’t get me wrong, Djozz’s tests are great and his latest setup is much improved but these numbers in particular just don’t correlate with real world results. I won’t take a guess as to what caused the high numbers.
The only directly comparable test me and Djozz have publicly posted are the 3rd gen square test where we both tested LED’s from the same reel:
1560 / 1480 = 1.054 Or 5.4% difference in output.
We also compared a few other LED’s via PM and we consistently came up with a ~5% difference.
Put simply the only way to compare these between setups is by testing with the exact same LED’s from the same reel.
We have done this and we have talked about it and ~5% is what the comparable tests came out to.
This is not an issue of weather our tests match up, that doesn’t really matter. What matters is that so far everyone that has built a light using the LED’s in my tests has posted results right in line with the results I got. So thus these tests correlate with the real world results people can expect. Which is the whole point of the tests.
This tells me that my hunch of not running with thermal paste would make the tests more real world accurate for flashlight use was in fact true and a resounding success.
I could not be happier with the outcome.