It is much higher than mine. Base on maukka’s review DATA, my average calibration# for TA’s tube is 0.6730133. The number is not 100% accurate because I know maukka did upgrade & recalibrate his integrating spheres several times.
I use most mid & low mode for more constant output from maukka’s review found on CPF and BLF. I choose seven stock lights same model & CCT as in maukka’s review to calibrate TA’s tube:
Lumintop Tool AAA Copper Nichia
Lumintop Tool AAA Ti Nichia
Zebralight SC600w HI Mk3
Olight H1 Nova NW
Olight S Mini Ti NW
Nitecore EC4SW
Nitecore MH20 NW
I wouldn’t use the Lumintop Tool AAA for any calibration as its driver has been known to vary wildly from one batch to another. I can remeasure the Nitecores when I have time to give you more accurate numbers. It was a long time ago when I tested them.
If I find time today I think I’ll try layering some DC Fix in mine, unless someone has tried it already. More diffusion, plus reduction. Might take several layers but worth a shot. The stuff is cheap, ~12 bucks a roll from amazon and I’ve got plenty of it here.
Here’s new output numbers for Nitecore EC4SW and MH20. Both with full 30Qs. Measured first on high, then on turbo, so the turbo numbers aren’t with absolutely topped off cells, since I had the high on for about 40 seconds. I did let the light cool off a couple of minutes though.
Seems my small styrofoam sphere I used when originally tested these was reading about 8-9% low. Still I think a 10% error margin is quite good for DIY integrating devices.
This is an option I was considering for a fix-all solution. Or some other similar film. Possibly cut out some acyrlic discs to fit in the hole the sensor goes and then add layers of the DC fix to it until the readings are correct. People can then install it. Although I have not figured out a good method for that yet.
While we’re all bouncing factory numbers around don’t forget that the variation among LEDs in any single flux bin is something like 12 or 15%, so Nitecore may say a light makes 1000 lumens but each light made will actually vary along a range of output depending on the efficiency of that specific LED and where it falls in that bin range. The only way that I can think of to calibrate these tubes to within less than the binning variation is to either sample many many many specimens of the same light and average them, or better yet to compare the tube’s readings against a NIST-calibrated sphere using the same exact light source, not another specimen of the same model. …which is what I tried to do using the HDS lights because supposedly they do that for each individual light sold.
Exactly what I have been preaching for years, the 14% tolerance from Cree on their LED’s inherently means you can’t get better then that without a ton of measurements.
On top of that you have the tolerances of all the components on the drivers, while 1% is common for some things 5% and even 10% is common others. Also the tolerances can compound on each other depending on how the driver is setup.
So 5-10% for the driver / rest of the light fluctuation and you can easily have a 20-25%+ variance strictly due to the tolerances of the components in the light. Then you have the environment factors, this can be seen more with throw readings at distance but it will still play a role in the tube readings. I can see a few lumen change in readings on very humid days vs dry ones.
There is no calibration factor on the lux meters. The tubes are (supposed to be) physically calibrated with diffusing material so 1 lux = 1 lumen on the meter. Fixing them will require physical modification to correct the calibration.
Oh, if only it was that simple, the last month of work would of only taken about a week lol.
Each sphere had to be individually “calibrated” by changing things like what diffusing sheets, how many, what direction they pointed, adding or removing reflective tape ect. All of them were different for reasons I can not explain. Not massively different but enough to cause each one to need a unique setup.
In this case since we only want to reduce the lux on the meter and we are not worried about diffusing the beam and making it even, we can put something just over the meter that should not suffer the wide variances.
The question is what to put there. DC fix is a possible option.
I cant wait to get my tube… i got many lights… my main testing with be stock lights and skylumen lights… i will be testing variety of lights, small, big, flood, and thrower.
So to reduce the amount of light hitting the sensor to re calibrate, the extra diffusing material needs to be right at the sensor? Isn’t there a diffuser plate near the front where we place the light? (I haven’t received mine yet so I haven’t seen it) Couldn’t we just add more diffusion material there?
I suppose when I get the tube (ETA Monday) it would be best to take measurements with ANSI rated lights? I have some Eagletacs I can try that have ANSI specs listed. Also is there one light that most of us own the same model we could be test to between us to compare, such as Q8?