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

It’s definitely tricky. You want an opening sized just right. Both my TA Tube and JoshK Sphere have large openings with 4 or 5 adapters that have different inner diameter holes. This seems to work well. It also allows you to move the flashlight head in and out of the opening.

I’d like to have a big 6” adjustable aperture that was chrome plated on one side.

I don’t think they are made that big, though. Probably really expensive if they were available.

The latest revision of the Bobbersphere. Still not sure how well it does on different beam types, waiting on a more throwy light from maukka.

Extech LT45 meter with custom factor setting and laser cut discs that Texas_Ace uses on his tubes:

Internal baffle + diffuser:

OK so a quick redesign of my tube to make it bendier, and I have the following multiplication factors. There’s two sheets of diffuser in the middle.

BLF 348: 0.113
S2+: 0.126

With these multipliers, it gives the following results which are all too low. All are full power / turbo on freshly charged high current batteries. I’m pointing the light just inside the entrance and using the white cutout to close the hole a bit.

Olight M2R Neutral White: 1379lm
Olight X7R Marauder: 8316lm
Emisar D4S XP-L HD 3D: 3480lm
Emisar D4V2 SST-20 5000k: 3108lm

Improvement suggestions welcome.

It seems that your setup is biased towards cool (or low CRI) or throwy since the factor is much higher on the S2+. Also this would explains why the wide floody beam of the optics in the Emisars read low.

Did you use the average of those two correction factors for calculation. The S2+ factor would be more pertinent to the Olight M2R calculation. That one doesn’t seem too far off.

I changed it to the average now and it still shows the M2R as 1458 which is about 150lm low, and the X7R as 7887 which is about 4000lm low!

With the S2+ as the calibration reference, the M2R would read 1537 lm which would be pretty much bang on. I measured it at 1500 lumens which is what Olight also specifies it at. The X7R is much floodier, which explains part of the error, but my sample wasn’t near 12000 lumens either.

Thanks. So you think my design is biased too much towards lights with a tighter hotspot?

Measuring my BLF A6 yields 1172lm

My Astrolux C8 showed 1373lm

My S2+ with Samsund LH351D only 801lm when it should be a lot higher. But that’s neutral white and a lot floodier

It isn’t as consistent as I’d like :frowning:

My S2+ with 8x3175 and XP-L HI does 780 lumens so 800 lumens for LH351D seems reasonable. My A6 with XP-L HD 3D is 1200 lumens.

My LH351D S2+ has an A6 driver… Should have said!

My A6 has a cool white XP-L HI

Wow, thanks for sharing this
My recently built lumen tube was reading almost the same numbers with a S2+ XPL HI-4B with 8*7135
I thought it was reading a bit low, but for other lights with given numbers, all my measurements weren’t to far off. It seems my setup is better than i thought !

I have tweaked the setup, this was the initial build

I’m pretty sure his LX1330B lux meter is a bit more sensitive to cool white than it is to warm white (same for HS1010A). If your testing a cool white light, use the 0.126 factor and if measuring a warm white use the 0.113 factor. If the light is neutral white, use a factor like 0.120.

Most of my lights are CW with a few NW, so I set my lumen tube for CW readings. If I do measure a NW light I try to remember to add a little more to compensate. I forget the correct number, but something like 3 percent. WW might read 5-6 percent low.

That certainly looks better. You say you put two sheets of diffuser material in the middle? They are probably acting like a single sheet. It would probably be better to spread them out. That way you have partially diffused light coming from the first one and then hitting the 2nd sheet to further diffuse it.

I am trying to find out what others have measured the x7r turbo at. 31% below spec seems pretty big, but might be accurate. Manufacturers often over rate their products output, but I thought olight would be a bit closer than this.

Okay, it seems Maukka has tested the x7r. It was tricky for him to measure because the proximity sensor would reduce output. He measured 3 lower levels in his sphere, then measured all levels outside the sphere, I’m guessing like a ceiling bounce. Then he matched up the 3 lower levels and calculated the upper levels. He also says the 12,000 lumen rating from Olight is at Turn On, not 30 seconds. :disappointed:

Maukkas Turbo S measurements at 30 seconds were 9,700 lumen. Your still reading about 14% lower than him. Maybe the proximity sensor is reducing output? IDK.

M4DM4X shows his honking tube which seems to be reading in line with the calibration lights. Good job!

I’m impressed that M4DM4Xs light meter will read both the cool neutral white perfectly. My LX133 has a bit of a variation between

I asked him about this as well. He has different lights. His S2+ is using an SST-20 in 4000K and the blf 348 has a 219C in 5000K. So they are much closer in cri and color temperature than Maukka’s earlier lights. This explains why they both read so closely to spec.

i hope with a calibration "in the middle" (4-5000k) the error towards lights outside that window is small

i will not say my numbers are carved in stone - but a "as good as posssible" field-test

Since your setup for high cri and NW, I would say your reading the lower end of the spectrum and are fine for WW and NW. If you measure low cri CW I would subtract about 5%. I think this is the number we found using the HS1010A like you have.

I am interested, and I pm you today already.

OK, I just ordered lights. Thank You “maukka” :+1: for your hard work and dedication providing us with these Calibration Lights. :+1:
Now I need a suggestion on plans to build a lumen tube. :question: :slight_smile:

See this thread Texas_Ace BLF Calibrated Lumen tube