I think the PM was probably the best way, My thought was if he had a stock light sitting around he could test and sell for maybe a little over the actual cost. I think he would understand you don’t really need one of his lights but just something to use for a calibration standard. My thought was maybe he would be willing to help since he’s a member and not that far away. (Georgia?)
“My testing: I use the FL1 test procedures, but my sphere is not ANSI calibrated but is calibrated using a number of ANSI rated flashlights. Since I make customs, I don’t have a production run of flashlight to test. I test each flashlight I build and report the output for that light. I believe this gives you the most accurate output rating for the actual flashlight you will receive. Many of my buyers have commented on how much brighter the PFlexPro flashlights are compared to the ones they have that were supposed to have similar output. I also provide full information on my methods of thermal management and construction details in addition to the actual output -I believe you have the right to know what you are buying.”
The 120 lumen difference is from using a .65 correction factor. We all know the stock C8 does not put out 1330 lumen so I adjusted the numbers down. (BTW, I might have read 1140 was your reading)
1330 = 860
1150 = 750
Difference of 110 lumen in real world.
If we use a .70 correction factor the difference is 125 lumen (930 and 805). I hope this makes sense.
I am not putting any material over the sensor. These are raw numbers so they can be adjusted later on once TA has an official correction factor.
What’s interesting is that Cree rates their bin numbers with a 14% deviation and then TA Tubes are calibrated within a 10% deviation. So both of our outputs fall easily within that range. Even if our tubes were perfectly matched, I might have an emitter on the higher end of the bin scale and you might have one on the lower end and it just fits within Cree’s 14%.
Yeah, it’s not very useful and I don’t mean to sound harsh. I just don’t want other people to get confused by it.
Handing out these Lumen Tubes is kind of like handing out a loaded gun. Some people know how to use it properly and will holster it with the safety on and other people will just run around shooting it off in the air with no regard to others.
That might be a bit of an extreme anology, but I think people should be more responsible when posting lumen results. You never know when an outsider might Google search for a flashlights output and go to a persons post that shows out of context numbers.
I know we are all amateurs here and these tubes are not meant to be a replacement for a proper integrating sphere (Ozzy), but I would still like to see us set some standards. Such as saying whether these are raw numbers from the TA Tube or if it has been corrected by XX%.
“I want these tubes to reduce the chaos in the world, not to create more.” - Philosophy of the day by JasonWW
You didn’t sound harsh Jason & I understand Newlumen’s excitement also…. nothing wrong with that.
But any data, without stating the parameters under which it was achieved; becomes random & meaningless. And that applies to most anything and anyone who does it.
It can be easily misinterpreted by someone looking at a random post where the parameters under which the data was achieved are not stated.
No harm, no foul. Maybe we can all be more responsible in what we post so as to contribute useful data.
We dont know the real correction factor… i dont have an integration tested light to calibrate… so jason, my 4” tube correction factor would estimate around .84… without plastic! Lol.
Just curious, what are you basing that estimate on??
IIRC that is the highest correction factor mentioned yet by anyone, seems like TA mentioned a correction factor of around .70 would get these in the ballpark until he could get a more correct one worked out & established from known light sources.
As now i only have fenix tk15 rated 1000 lumen. This light could be 1004 lumen, 1050 lumen, 1090 lumen, anywhere from 1000-1096 lumen… we are not suppose to be using stock light to calibrate…
Personally, I do not have a light with verifiable tested lumen output. So anything I did would just be a shot in the dark… a crapshoot so to speak.
So, therefore I will just wait until the verifiable correction factor data is worked out by TA and/or the guys who actually have verifiable lights to test.
Although after reading the PFlexPro site yesterday, I may spring for one of those tested & verifiable lights in the not to distant future.
Honestly until I am able to get some calibrated lights for more exact numbers (or if someone else has some like that), I would not really worry about getting it exact.
Just post the as-is numbers and maybe some numbers with whatever method you found got them in the right ballpark.
All I am looking for now is the average correction factor among the spheres at this point. So far it is looking well within my goal tolerance levels but more data is always good.
You are welcome to adjust your sphere however you want and to whatever you want for now. Once I figure out a fix then everyone can apply it and compare readings evenly (well, within ~10-15% or so, with everything factored in).
Very good, it looks like they are averaging out very good sphere to sphere. That is the hardest part by far so I am very pleased with those results thus far.
Okay, so the raw number was 4111 I think. I remeasured mine at 30 secs with a Liitokala and got 4490 x .70 = 3143 so we are very close. Within 10, which is well within Cree’s 14 tolerance.
Are you using a protected battery? I’m not sure if that will effect a boost driver, but it might. Our numbers might be even closer if we used the same battery.
Got to remember that not only do you have the 14” tolerances of the LED to factor in but also the 1% (resistors are usually 1) to 20 (capacitors, coils and other such components range from 10% to 20%) tolerances of the components on the drivers.
On top of that and many of those tolerances compound on top of each other. Particularly with buck and boost drivers as they have a lot of components that factor into the final output.
This is why using random lights off the assembly line is so inconsistent and hard to calibrate a sphere with.
Here are some fresh numbers from most of my lights. All CW.
Some interesting notes are that I lost 23% output on the X2R by switching the reflector to a 60° TIR lens. So to go from my headlamp measurements, which both use the same 60° lens, I need to add 30% which I did at the bottom.
The new Boruit 5K headlamp is kicking some butt. It’s rated at 5000 lumen, but that is Chinese lumen so completely unbelievable. I think the predecessor RJ02 was only about 300 or so lumen, but this one is an estimated 650 lumen. Not bad for a no name emitter.
Most of my lights match up to the JoshK Sphere by the same general percentage. The C8 was off quite a bit. I wonder if it’s due to the narrow beam.
The L5 and L6 are my custom lights which is why they are reading very high.
