Texas_Ace BLF Calibrated Lumen tube / Sphere No math skills needed - Several spheres still available

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Newlumen
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I just message with vinh. Skylumen… nitecore lumen are after 30 seconds..

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Got mine today, had not tracked so was surprised.
Have to say lately I have been bored with flashlights and real life has taken over my time. But after opening the box and setting it up I was grabbing all kinds of flashlights that I have not handled in 6 months to try them and think the readings are pretty good.

First one tried was trusty old Sofirn PF04, EDC it every day and it came up as 236 lumens, they rate it at 240 and Sofirn is usually fairly honest on their readings or a tad under rated so that was a good first try.
Next up was a C8 by SeresRoad which is pretty much a Thorfire C8 XML2 that came in at 1090 lumen pretty much what was expected.

Also tried a Sofirn SP32a, showed 1350 with Panasonic utility battery, tried a Samsung 30Q and it went over 2100, the meter auto-ranged up at that point and read 210.
Did not keep it on for long as that light gets hot quick in turbo and didn’t want to risk frying the emitter. That is why I run the less powerful battery in it for safe daily use.

So, so far I like this rig.

Told the Wife it is a “Precision Measuring Device” and not a new toy Smile
Anyway Hat’s off to Texas_Ace and his “Team” for delivering the goods ahead of time and on Budget.
I feel blessed to have gotten one at the price paid and am happy for not being pessimistic.
THANKS!!!
Later

Keith

After the Apocalypse there will be only 2 things left alive, Cockroaches and Keith Richards
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Choosy Mother’s Chose Jiff!
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JasonWW
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I got mine just now.

I’m also surprised by the high readings compared to the JoshK sphere.

I have a Convoy S2+ with QLITE 3A driver and xml2 CW:
JoshK 700
TA tube 1350

On the Road M3 CW: .69
JoshK 862
TA tube 1240 (4v)

Convoy C8 xml2 CW: .65
JoshK 845
TA tube 1310

DQG Tiny 7× 2500lm:
High- .65
JoshK 855
TA tube 1310

Turbo- .64
JoshK 2120
TA tube 3300

These are just quick tests with some batteries at 4v or so. I won’t be able to do more accurate measurements with fully charged cells until tomorrow.

I think the general consensus is that it is indeed reading high.

I tried covering the reflective tape on the spacer ring with black cloth, all I had at the moment, and readings seemed to drop back down to a little above the JoshK sphere. Maybe painting the silver side with flat black and flipping the discs will get the readings in line. (Maybe, requires more thought)

I was a bit skeptical of the JoshK sphere because after measuring lots of lights with it, the readings always seemed a little on the low side. Maybe once you take into account losses in reflectors and lenses maybe it IS accurate?

Anyway, all this will have to wait till later for me.

(NOTE, My JoshK sphere numbers are from a past session. I was comparing that to today’s measurements in the TA tube.

So not a direct comparison. I’ll get both spheres set up tomorrow so I can do back to back tests)

Newlumen
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Keep the TA specs number coming.. i will put out my numbers on tuesday.

emarkd
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Mine also came today. Its a really cool design and well put together so I’m excited to get it dialed in. I also have a JoskK sphere for comparison, so I ran some quick numbers as well

Light/host Spec Sphere TA Tube Diff
HDS 170 170 168 234 71%
HDS 200 200 203 327 62%
ReyLight Lan N/A 234 327 62%
Swm V10r 219c N/A 315 474 66%
Haiku 219c N/A 390 609 64%
Zebra SC5c mk2 475 427 648 66%
Hanko 219b N/A 615 890 69%
Zebra SC62w 930 891 1362 65%
Zebra SC63w 1150 1086 1748 62%
Zebra SC600w mk2 HI 1126 1120 1738 64%

So a few important points:

  • Like Jason I didn’t bother to test cell voltages because we’re comparing measuring devices here, looking for relative numbers, so it really shouldn’t matter just to try and find a trend. But maybe it will when trying to compare to other users’ numbers so I may need to re-do this when I have more time.
  • The HDS lights are the most interesting to me, because according to Henry at HDS each and every single light is custom calibrated on his sphere to give the promised output. He tweaks the levels in the firmware so that the lumens are exactly as promised, so they should make pretty good “reference” lights for these sorts of tests. Unfortunately (for this application) I’ve modded most of mine which invalidates that work, but these two are still stock.
  • I’ve included “spec” numbers for factory, unmodified lights. They’re just there for reference and not included in the math. Lights marked with N/A are modded in some way so factory numbers, if they ever existed, would be useless.
  • I’m concerned that my differences don’t show a more precise trend. A range of over 9% difference, between the lowest and highest variations, seems like a lot to me. I suspect my “technique” is to blame there which makes all my numbers questionable. I’m still trying to figure out the best way to use this thing.
  • I didn’t include any “high-powered” lights for this test because the JoshK sphere can’t handle them, so I’d have nothing to compare to. If the tube’s response isn’t linear then it may not be off as much at the higher end. I have no way to test that. I did order those numbers above in lowest -> highest order in the hopes of seeing some sort of trend in the differences, but I don’t.
  • More data is definitely needed but I think its safe to conclude that the tubes are reading high, its just a matter of determining how much high. Mine seems to be up by ~35%. I’ve not yet tried to bring it down in any way and look forward to what some of the rest of you come up with.
JasonWW
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My JoshK sphere numbers where from a past session. I was comparing that to today’s measurements in the TA tube.

So not a direct comparison. I’ll get both spheres set up tomorrow so I can do back to back tests.

I’m really impressed with how the depth of the flashlight through the opening as well as the angle of the flashlight in the opening doesn’t vary wildly.

You basically just want to aim your light straight down and then move the flashlight up and down a little bit to get the highest results. It’s working really well. Big Smile

Newlumen
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Maybe we can watch matt video and use correction factor method of calibration.

https://m.youtube.com/watch?v=xOE1ykJ5WAU

Newlumen
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charles lin wrote:
I received mine today. However, I doubt about accuracy Sick

Nitecore tip CRI measure 320 lm?? factory spec: 240 LM

Hey charles, try this method.

Turn your nitecore tip for 30 seconds on the lumen tube.. then you will get the lux number..

( 240/lux ) = number A.

Number A is your main number…

Put any lights.. lux * number A = lumen

Man Without Shadow
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I don’t have a horse in this race, but what ever is done to adjust measurement should be similar or consistent with TA’s tube and/or with replicable readings among each of the 30 tubes out there. I am not suggesting one not have fun playing with their own tube, but it seems an important part of having 30+ tubes out there would be that they have similar measurements and a kind of “standard” between them.

It would be nice if everyone had like a “calibration” light or set of lights that would be used as a standard starting point and assuming every similar light was putting out similar lumens (maybe thats impossible…). Maybe there is like one “right on the nose” light everyone might have (BLF Q8?). Everyone blast your “calibration” light in there, calibrate it to an agreed upon or “defined” lumen output, and see if that lets others measure other lights with any consistency.

Could like everyone use some kind of AC lamp with a set rated lumen output, some LED light bulb or something as a cheap and easy to get standard? Everyone buy the same exact LED bulb and go from there?

I suspect my idea is maybe too simple for the sophisticated optics behind tubes and lumens.
I suspect TA will have a better and simpler way to address the calibrations if necessary.

I just like to learn stuff…

When I'm spending mony foolishly, I like to do it wi$ely...

I have all the flashlights I need, but not as many as I want...

 

JasonWW
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Obviously we can figure out a correction factor to use, but I would like to keep the design premise of having a direct lumens reading with no math involved.

Before any modding, the important thing is for the owners to not permanently alter the calibration that TA put on the tubes. So I was trying to figure out a way to reduce all output by a certain percentage.

Maybe making the centering discs do double duty is an option. Keep the reflective tape on one side, but change the silver paint to a less reflective color on the other side.

Instead of repainting, maybe cover the painted side in an adhesive backed felt in a specific color such as black or brown. Felt might be more consistent than paint. The problem with altering the entrance of the tube is that different beam shapes may be affected to differing degrees.

If we need a 50 or 60 percent reduction in output across the board, then we might need to look at the sensor end of the tube. Maybe a thin sheet of tissue paper over the sensor and then stick it in the hole would get the job done. This way you could still have TA’s calibration and then have your own calibration which might be closer to accurate.

So a theory – TA buys a stack of tissue paper, like waxed for instance, tests it out, gets a proper reduction across the board for all light types, then mails out a few sheets to all owners. Maybe we send a few bucks to cover envelopes, stamps and the extra effort. Then everyone’s lights would still be calibrated to each other. Plus we could simply remove the single sheet of tissue paper over the sensor and be right back to stock.

Just a thought.

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 Also seeing numbers higher than expected. Measurements taken 30sec after turn-on:

 

Fenix PD35 (freshly charged Samsung INR18650-25R)

spec high = 1,000

TA Tube = 1,600

 

Acebeam X80 (freshly charged Acebeam 18650s that came with light)

spec medium level =  2,500

TA Tube =2,850

 

Zebralight SC600w Mk III (freshly charged Samsung INR18650-25R)

spec high (H1) = 1,126

TA Tube = 1,725

 

Nitecore TIP 2017 (non CRI version) fully charged built-in battery

spec high = 150

TA Tube = 202

spec turbo = 360

TA Tube = 448

 

J5 Tactical V1-Pro (Olight 14500 battery)

(note, many have suspected they fudge their numbers)

spec for high = 300 

TA Tube = 210

 
Olight S1 Baton (fully charged Olight 14500 battery)
spec high = 500
TA Tube = 730
 
Olight S1A Baton (fully charged Olight RCR123A)
spec high = 600
TA Tube = 797
 

Nitecore TINI (fully charged built-in battery)

spec high = 145  , TA Tube = 217
spec turbo = 380 , TA Tube = 545
 
Olight I3e silver (Panasonic Eneloop Pro AAA)
spec single mode = 120
TA Tube = 173
 
Olight I3e copper (Panasonic Eneloop Pro AAA)
spec single mode = 120
TA Tube = 167
 
Olight I3e blue (Panasonic Eneloop Pro AAA)
spec single mode = 90
TA Tube = 128
 
Olight ION (fully charged built-in battery)
spec high = 320
TA Tube = 447
 
Adventure Sports Flashlights custom Maglite (2X KeepPower 26650)
spec high = 5,000
TA Tube = 6,550
 
Rofis ER3A (Panasonic Eneloop Pro AAA)
spec single mode = 120
TA Tube = 145
 
MecArmy X4S (supplied 10180)
spec high = 130
TA Tube = 158
 
Klarus P20 (2X Panasonic Eneloop Pro AAA)
spec high = 230
TA Tube = 325
 
Averaging multiplication correction numbers for all results (excluding the J5 for obvious reasons) gave me a correction factor of .728(

I also noted that the exact position of the light made little difference.

Quote:
I’m really impressed with how the depth of the flashlight through the opening as well as the angle of the flashlight in the opening doesn’t vary wildly.

My reviews: , My personal collection of lights LINK,  J5 Tactical V1 Pro review LINK,  Thirteen Optical Sensors review LINKZebralight SC700d review LINK,  Ray-O-Vac Super Power Sportsman review LINK,  Convoy S2+ color combos LINK,  How To flash D4V2 LINK.

maukka
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FWIW my SC600w HI Mk3 sample reads within 0.5% of Zebralight’s claim of 1126 lumens at 30 seconds with any good battery (VTC5A, VTC6, 30Q, GA). I’d use that as a good calibration light for that type of beam.

edit: to clarify, this is in a sphere, not in TA’s tube, which I don’t have

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Wow, no one seems to have the same lights as me. Here is what I can measure (that are still stock).

Convoy S2+ with QLITE 3A driver and xml2 CW

Convoy C8 xml2 CW

On the Road M3 CW

OTR U16 CW

OTR U18 CW

DQG Tiny 7× 2500lm CW

Eagle Eye X2R CW

EE X5R CW

Lumintop ODF30 CW

Lumintop Tool AA CW

Lumintop IYP365 CW

Jaxmnve M3 CW

New Boruit 5000lm headlamp

Crelant CH10 Xml2 CW

Zanflare F6 and F6S CW

If anyone else has one of these lights, let me know and we might be able to do some direct comparisons.

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Wow your lights are all CW. I always thought you were a WW guy from your username. I have NW versions of some of your lights but can’t really compare them if they are not the same CCT. Might be different flux bin too.

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If someone in Europe (shipping stuff back outside EU is too expensive) has the integrating tube and wishes to calibrate it against a sphere, PM me. Sending me two of your own lights with preferably different CCT and CRI and beam profiles would be much better than trying to calibrate against a different sample of the same model.

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maukka wrote:
FWIW my SC600w HI Mk3 sample reads within 0.5% of Zebralight’s claim of 1126 lumens at 30 seconds with any good battery (VTC5A, VTC6, 30Q, GA). I’d use that as a good calibration light for that type of beam.

edit: to clarify, this is in a sphere, not in TA’s tube, which I don’t have


Maukka, Could you explain why my SC600w HI Mk3 measure 1680 lm@30 seconds in TA’s tube (Zebralight’s spec: H1-1126 lumens), but I got Exactly same M1-61 lm @30 seconds in TA’s tube as Zebralight’s claim??
maukka
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The M1 on mine is actually 46 lumens.

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maukka wrote:
The M1 on mine is actually 46 lumens.

Thanks! now It makes sense!
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emarkd wrote:

  • I didn’t include any “high-powered” lights for this test because the JoshK sphere can’t handle them, so I’d have nothing to compare to.

You can try putting a neutral density filter inside the sphere over the sensor. I then took a few readings (under 1000 lumen) both with and without the filter to get a correction factor. Then I could measure my brighter lights. At least the ones that would fit in the hole.

The JoshK sphere is also set up to put a high powered light on the outside of the ball to shine in. There is a shield inside for this purpose. It also uses a different method of calculating the output which I’m not familiar with. I need to re-read the thread and find those instructions.

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I’m getting high readings too.

Might have a solution to the problem.

I tried it without using any of the rings. I just hold the flashlight centered right above the lip of the tube.
I didn’t try all my lights but the reading seems to be a little more accurate.

Zebralight light – spec 1163 – reading 1803 – w/o ring 1233
astrolux c8- spec 1300 – reading 1650 – w/o ring 1121
mt09-35 – TA tested 7000 – reading 8090 – w/o ring 6980
Surefire Fury – spec 500 – eading 883 – w/o ring 615

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after more testing. I notice that small lights under 1” dia cannot be tested without using a ring.

with smaller flashlights, you’ll need to use a ring that will give you about 1” of opening on all sides to get a decent reading.

this is only mine finding. might not work for all.

JasonWW
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I tried it without rings too, that’s what gave me the idea of coating the underside of the ring black.

I don’t think it’s going to be a practical solution because it won’t be consistent between floody lights and throwy lights.

I think we have to have that reflective tape to help trap all of the light.

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Sorry I was not around last night, still catching up.

I have suspected the readings are a bit on the high side before, which is why I always round down but never even considered them being this far off. I figured maybe 10%.

I went back and looked at my notes on the calibration process for my sphere from 2 years ago and did realize a few important details I completely forgot about.

1: I was having a horrible time getting readings to agree with basically anything, the more lights and LED’s I tried, the worse it seemed to get.

2: I ended up getting so frustrated I decided I trusted the Cree spec sheets more then light ratings and ditched basically all of the light ratings except for basic comparisons.

3: I started testing all the LED’s I had on hand, which at the time were basically all from china sources like Fasttech.

At this point I think many of you can see where this is going. I was still fairly new to the raw LED market back then and put far too much trust in the ratings from fasttech and others. One thing that stood out to me is I see some notes about XP-L HI V6 LED’s (I was/still am a big XP-L HI fan).

I now know these do not exist but these played heavily into my testing at the time as they were the LED I was buying and using the most.

So I was using the cree data sheet for a V6 emitter when they were at best a V2. This also explains why other LED’s read much too low.

According to my notes I ended up averaging the numbers and settling on that as my final calibration. This put the few stock lights I had around the expected output as compared to other BLF numbers. For example my A6 at the time got just over 1600 lumens on an HE2 battery, although the notes do not say if the springs were bypassed.

Basically I think I royally screwed up the calibration on my sphere but due to lack of comparable numbers could never figure this out.

It reads lower then many I know for sure so I never expected it to be so high.

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maukka wrote:
If someone in Europe (shipping stuff back outside EU is too expensive) has the integrating tube and wishes to calibrate it against a sphere, PM me. Sending me two of your own lights with preferably different CCT and CRI and beam profiles would be much better than trying to calibrate against a different sample of the same model.

This would be great if we could get a direct comparison. I am really bothered that the readings are not even close to being correct. Feels like I mislead people when that was the last thing I wanted. I simply didn’t have anyway of getting better numbers.

I know one went to Sweden and 1 to the UK but that is all to Europe.

Maybe I could send you a few lights to get real lumen readings, then you can send them back and I can compare? That way I would have standard lights to calibrate the ones I still have and re-calibrate any that people want recalibrate.

I have wanted to do this for some time, even looked really hard for a real sphere to get a “calibration light” when I was building mine but could not find anything.

Terry Oregon
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TA, in order to make this project work as expected, is it safe to assume that:

 

(1) after measuring several lights from respected manufacturers, each of us could come up with our own correction factor, and end up with relatively accurate readings?

(2) that correction factor should be about the same for everyone?

 

Based on four of the lights I've measured so far (from respected manufactures), my correction factor would be .72

Using a correction factor only takes a few seconds to compute, really no big deal.

 

 

My reviews: , My personal collection of lights LINK,  J5 Tactical V1 Pro review LINK,  Thirteen Optical Sensors review LINKZebralight SC700d review LINK,  Ray-O-Vac Super Power Sportsman review LINK,  Convoy S2+ color combos LINK,  How To flash D4V2 LINK.

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Terry Oregon wrote:

TA, in order to make this project work as expected, is it safe to assume that:


 


(1) after measuring several lights from respected manufacturers, each of us could come up with our own correction factor, and end up with relatively accurate readings?


(2) that correction factor should be about the same for everyone?


 


Based on four of the lights I’ve measured so far (from respected manufactures), my correction factor would be .72


Using a correction factor only takes a few seconds to compute, really no big deal.


 


 

Yes, that would work but a “standard” correction factor for everyone would keep all the numbers comparable. For that we need as large a data pool as possible and then to average the results.

If I could get some lights measured by a real ANSI sphere for calibration proposes that would be great, then for the first time I would have a standard I trust to calibrate my sphere and figure out a correction factor for everyone.

As I am sure many have noticed, lights vary a lot from the ratings. They may be ok in some modes but it is quite rare for them to be correct in all modes with all batteries.

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I have many more lights I want to measure, to fine tune my correction factor.

 

For those of you who have been into flashlights longer than me, which manufacturers could I trust the most for accurate lumens outputs?

Someone mentioned Fenix. The three I have are PD35, FD40 and FD20.

Or any specific models that have been tested by a reliable source?

My reviews: , My personal collection of lights LINK,  J5 Tactical V1 Pro review LINK,  Thirteen Optical Sensors review LINKZebralight SC700d review LINK,  Ray-O-Vac Super Power Sportsman review LINK,  Convoy S2+ color combos LINK,  How To flash D4V2 LINK.

JasonWW
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I may be on to something. I remember reading somewhere about someone using tissue paper in there lumen tube. Maybe it was TA?

I grabbed an extra waxed paper from donut section of the grocery store this morning. One piece over the sensor dropped it a little, two pieces were closer and three pieces seem just right.

Now the tube is reading pretty much the same as the JoshK sphere or just a tiny bit higher. Assuming that’s what we’re aiming for. Also, the amount of time the light is on before taking the reading does make a large difference and might explain why it’s not exact.

Here’s how I measured my BLF GT. I used a C8 reflector. I then stuck it in the appropriate sized ring. LOL. Silly

GT in TA tube:
Stock tube – 3300 lm – obviously too high
3 layers – 2200 lm – pretty realistic

I know it’s not the same without the big reflector and lens, but that doesn’t fit on the 3” tube. No biggie. It’s the only light I have that doesn’t fit.

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The reading is about 1/3 higher than what is expected. We’ve seen this value before. The 4” tubes were measuring 1/3 lower, which is related to the fact that a 4” tube
has 1/3 more surface than a 3” tube.
Is there perhaps some kind of mix up?

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hIKARInoob wrote:
The reading is about 1/3 higher than what is expected. We’ve seen this value before. The 4” tubes were measuring 1/3 lower, which is related to the fact that a 4” tube has 1/3 more surface than a 3” tube. Is there perhaps some kind of mix up?

The final calibration on all the tubes should be the same +/-~5%.

Although I do agree that it is looking like the calibration that I am using is indeed about ~30% too high.

I just need to get some hard data / more data and we can come up with a hard value for a correction factor.

After look at my notes from 2 years ago and applying what I have learned in that time, I am not as surprised that the readings are high, although I am VERY surprised they are so high.

Luckily it is easily correctable once we figure out a good correction factor.

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