WTS: Calibration lights for DIY integrating spheres / lumen tubes - 67 € -

I’m super happy so far. I plan to test with fresh off the charger batteries over a few days to make sure i’m getting the same readings. Used an eneloop fresh out of the package with a 17-10 stamped on it, and a 30q that’s been rested for a few weeks.

Originally, I calibrated my sphere using a few lights I thought were pretty good to go. A GE led nighthawk floodlight (residential ac model), and a few off the shelf lights from olight and nitecore.

I ended up with a rounded multiplier for my 17”, BaSO4 coated, paper mache and fiberglass sphere of 0.20, using a Dr Meter LX1330B.

Initial tests using the newly received calibrated lights gave me 0.1965 for the NW BLF348 and 0.2085 for the CW s2+.

I will likely extrapolate the new variable multiplier, using a formula, based on color temp for all my other lights. With fixed points at the 6420k and 4862k my test lights read.

This is super exciting.

Here’s what i’m using:

New sphere

I’m surprised those off the shelf lights got you so close. It seems for most people their calibrations end up reading too high.

The olight s10riii and m2r warrior are pretty close to spec. nitecore p12 was all over the place, based on the light’s setting.

I also measured and logged the blf a6, klarus mi7, a few streamlights, and a bunch of s2s, s2+s, c8s, l6s, l2s, q8s at all levels of modding, emisar d4, and a dozen or so others.

I weeded out the outliers and the ones that didn’t measure consistently, then averaged and averaged again. Then compared to all the reviews I could find on each light (some good (with fairly accurate lumens) and some not so good).

Luckily, I saved all my spreadsheets with raw lux numbers measured at start and at 30s, so now I can apply the appropriate new multiplier and have good data from this sphere.

Until the calibration lights, I was always pretty let-down by my numbers, since they were pretty low compared to others’. TBH, the TA sphere reality-check (once calibrated) was a relief. It made the hours I put into it a lot more worthwhile, since my numbers were pretty close.

I analyzed raw data for a number of years at work. I was an analyst by title and job description. Finding outliers and determining trends keeps me up at night if I can’t quite figure it out. A few years ago, I moved into a position using the data (from other people now, although I check it often) to drive people’s workload, and it’s more of a hobby now in this form.

Now that’s a cool DIY sphere! Getting +–3% was pretty remarkable.

But isn’t it nice to have some confirmation on your numbers? I know the uncertainty killed me before. :slight_smile:

I know it sure caused me issues before I had these.

Having these lights a few years ago would of literally saved me 6+ months of tinkering with my sphere.

Finnish lights finnish their journey. Got mine today. Thanks again Maukka. Can’t wait to play with these guys.

My long anticipated package from Finland came today. Time to go dial in the tube. :wink:
Thanks Maukka for offering these great tools. :+1:

Maukka sorry for bailing on my order the other week. Sign me up again, my wife bought me a prepaid gift card to use since we don’t use credit cards in my household. I should not have an issue with waiting to pay. My apologies again.

My lights arrived maukka. Thank you again!! :beer:

Looking forward to using them……

Received my lights yesterday from maukka (thanks). All measurements were taken with the TA lumens tube correcting disks installed per instructions (oriented correctly).
maukka Convoy S2+
252 (TA tube)
262.3 (calibration sheet)
diff = 3.9%
maukka BLF348
35 (TA tube)

35.6 (calibration sheet)

diff = 1.7% (note the meter doesn't read tenths at this light level, so this is an approx)

My other calibrated lights:

PFlexPRO
505 (TA tube)
607 (calibration sheet)
diff = 16.8%

HDS Systems
213 (TA tube)
200 (calibration sheet)
diff = 6.1%
Conclusion: The Texas Ace calibrated lumens tube measures accurately within the rated 5%.

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 :wink:

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.