Nice results, Vresto and Terry.
I’m not a great fan of the tube design light measuring things, getting results truly independent of beam pattern of the light source does require a (well-built) sphere design, but I must confess that getting the TA tubes around the forum, and combined with maukka’s calibration lights, that seems to have helped hugely getting the calibrations on the same page.
Good enough for almost any BLF discussion, and the last few percent is too much pain to achieve anyway.
Thanks a lot for sharing your results! Getting results even within 10% between different setups is very beneficial to the community. Next step: bare emitters and aspheric zoomies for calibration 
Very nice! I am glad to see these are panning out as I hoped.
Agreed, a Sphere is the best method for sure for the ultimate accuracy.
Building and shipping them is a royal pain and the cost would be much too high for most people so it came down to a best bang for the buck option. Plus even though I had a sphere I found I used the tube more because it was simply easier to keep within reach as it could sit on my desk, the sphere was just too big to keep accessible.
For anyone wanting to take the next leap in performance Djozz has some great writeups on how to build a proper sphere that will get you are close as you can get to perfect.
Still working on ‘as close as you can’ though, not there yet…
Thanks terry.
I’m seeing the pattern that these HS1010A meters are reading NW (about 4500K) right at 3% lower than CW (about 6500K).
I think this means you can adjust the TA Tube to suit your preference. If most of your lights are NW you can tweak the correction discs to read spot on with NW. Then when you test a CW you know to subtract about 3% to the results.
If most of your lights are CW (like mine) you can tweak the correction discs to read spot on with CW. Then when you test a NW you know to add about 3% to the results.
If I test a light in between, such as a 5000K-5700K, I’ll add about 1.5%.
If I test a WW light, about 3000K, I can add maybe 4%.
Or if you test a mix of CW and NW all the time, maybe split the difference (so NW reads 1.5% low and CW reads 1.5% high) and just not worry about the differences.
Sounds good to me.
If your percentages are correct this is should work pretty well. Mind though that if high CRI leds are measured that the correction could be different again, even with same colour temperature. If all that is measured is standard 70CRI, it works as you suggest.
Yes, I have noticed this as well, the high CRI can read differently vs 70cri.
Seems odd. I don’t get it.
Certain wavelengths seem to trigger the lux meter more then others and the high CRI LED’s have a wider range of wavelengths so they read differently then the equivalent 70cri LED. Although it is hard to get exact numbers since you rarely see the same bin in both 70cri and 90cri.
It makes sense though when you think about it, it is the same reason CW reads higher then NW. Different wavelengths triggering the sensor differently.
Although as a basic rule of thumb you can add/subtract a few percent to get closer.
I got my CW S2+ calibration light yesterday. I needed to adjust my TA Lumen Tube down by 7%. More details in the Lumen Tube thread.
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I would like one of these kits. Please advise. Thanks!
S2+ (1329)
282 lumens at 30 sec. on TA tube
286 lumens at 30 sec. maukka calibration report
Difference ~ 1.40% (rounded to 3 sig figs) ± .01% (uncertainty)
My BLF348 (1129)
57 lumens at 30 sec. on TA tube
57.2 lumens at 30 sec. maukka calibration report
Wow, that is right on the money. I would not try to adjust anything to make it more accurate.
Yeah, I am satisfied with the results. Thanks Texas Ace and maukka!
Hi maukka, please pm me your paypal info and price… i am ready to purchase. Thanks.
I added you to the list. I’ll PM you with the details early next week when I have measured the next batch of lights.
Ok. Thanks.
So, I need some confirmation on my NW numbers. Reference numbers in yellow.
Does it make sense that the multiplier should be higher for the CW than the neutral? For some reason, I was thinking it would be the other way. Everyone says CW read higher, which makes me think I would need a lower multi for them, to bring them down.
Using a Dr Meter LX1330B in my sphere.
Getting an average of 0.1994 for the NW and 0.2081 for the CW.
The convoy light is very consistent with different battery voltages and light head temperature (back to back tests). The 348 is a bit more sensitive to the voltage and more so with the temperature (back to back tests always show lower numbers).
Do I keep digging or call it good?
Maukka, what voltage are your eneloops when you install to test? right off the charger (I get about 1.51v) or rested (I get 1.38v that way).
I also graphed (linear) the difference across color temps I have on hand. I’m hoping the linear relationship is a good way to go. Way easier with just two data points.