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

Received mine yesterday. Have not had time to test it out yet.

Thanks for making these TA.

I see a need in the flashlight world that isn't currently being fulfilled on an affordable/practical basis. Would be nice if:

(1) xyz company would test a specific light that you mail in - then test it in an integrating sphere - then return it - for a reasonable fee

(2) a flashlight manufacturer would sell tested lights with a calibration sheet showing that particular light was tested in a sphere. That might cost twice as much (or more) than a normal production run - but would be worth it as a reference.

As you can imagine, the price range is huge. Some compact ones like the Labpshere FS2 cost several tens of thousands. Last year I was contacting multiple sphere manufacturers specifically looking for an affordable one, which wasn’t an easy task. Most of them ignored my emails. Lisun however was very helpful and also provided photos of details I asked about to make sure I was able to do flashlight measurements easily.

It did help that I didn’t need the spectro or software, even though some mfgs always bundle them together. After some back and forth negotation, this sphere with the required equipment (meter, standard calibration lamp, psu, shipping + VAT/duty) only came to the level of couple highend custom lights (<$5000). A tradeoff I’m more than willing to make. We are at BLF after all. The sphere itself is well below $2k.

Of course if you don’t buy a package deal with all the associated equipment from the sphere company, there’s a lot of experimenting and calibrating to do, just like with any DIY integrating sphere/tube/shoebox. If you’ve ever tried building one, you know. You can get very good results with making everything yourself, but usually the meter is the Achilles’s heel. Djozz has several good threads on the subject. Also, measuring flashlights is more difficult than omnidirectional bulbs. But as this is a hobby, I don’t consider the time spent doing this costing me anything. Rather a learning experience.

I disagree completely, I’ve gotten very good answers that have helped me understand more about this and know how to use it better when it arrives, that’s all I was after.

.

Is that bothering you?
I’ve only asked a few questions not a ton, you’ve asked about the same number of questions today yourself. First time I’ve been chided on the forum for asking questions!!

I was thinking of a way to reduce this back and forth international shipping cost to Maukka drastically.

Maybe Maukka (I assume he has lots of flashlight parts laying around) could choose a suitable emitter and a reliable driver and wire it to a common battery (30Q) then record the levels in his sphere minus a flashlight body. Then he just mails that to TA. Wouldn’t the exact results be repeatable?

It’s also one way shipping of a thin envelope.

You guys would have to sort out the small details such as the size of the heatsink it’s mounted to and how long after turn on to take the Lumen reading. Maybe also how to hold the emitter to the sphere. So if Maukka says he measured this emitter/driver at 44lm, 160lm and 555lm then TA can measure in a couple of his tubes to get an exact correction factor.

Maybe you guys both have power supplies? Then you can use a set voltage and eliminate the battery as a variable.

Just a thought.

If the integrating properties aren’t perfect it’s better to calibrate using a light with a reflector, since that’s what the tube will be used for.

The S2+ on a med mode and the BLF348 are very stable so they’ll do fine.

edit: the power supply suggestion is good. TA could just send the head of an S2+ without a driver with leads hanging out from the MCPCB. If he has an accurate PSU we could just drive it at 100mA to take the battery out of the equation.

WOW! That's one heck of a great "Just a thought"! Big Thumbs Up, bud! :)

Not chiding. :innocent:

Let me know if you hear back, I will most likely be sending my lights in a few days but not having to ship international would be great.

I sent my lights today to Finland.

Now the waiting game start……

You said “affordable/practical” then comment that you’d pay double for this service. At the risk of starting to sound like an HDS fanboi lol, I’ll just point out again that they do this with every light they sell, except instead of providing a certificate of that lights output, which would just lead to pissed off customers who didn’t get the brightest samples, they tune down the high performers, tune up the weaker ones, and sell them all with the same exact certified output (but variable and undocumented runtimes). At least, that’s the claim and I have no reason to doubt them. And yes its costs double (or more) than most other similar flashlights, but I find them worth the expense. So while I agree it would be nice to see more makers doing this, you can have what you want right now.

thanks for that info, interesting . . .

[quote] HDS Systems is the only manufacturer to go the final step and calibrate each flashlight. We measure the output of each flashlight after it is completely assembled and adjust the output to produce the specified lumen output. This method allows the LED to warm up to operating temperature as part of the measurement process so the flashlight's true lumen output can be measured and adjusted under representative operating conditions. Thus, our 250 lumen flashlight can be counted on to actually produce 250 lumens. [/quote]

I think he meant something more like starting out with a Convoy S2+ for $15 and then getting it measured and then selling it for $30.
HDS is in a very different price category ($230-$300).

Maybe a tested light under $50?

Hi boss, do you have a list of light that you measured with your integration sphere?

I am getting my lumen tube today. Yay .

You can check my started threads after 7/2017. All the reviews done after have been made using the sphere.

I got mine last Friday, but have not had time to do anything with it yet.
It looks like rain today though so maybe I’ll have time to check it out further.

Well done TA, the tube looks well made!

Thank you……. :+1:

Out of curiosity, I emailed HDS and asked what equipment they use to calibrate each light. They replied right away.

I just received my sphere today too. The box was all wet because the USPS guy just left it at my door without ringing door bell last night. I won’t have time to play with it this week but will do so after and report back.

I got the lumen tube… is the flashlight bezel suppose to touch this thingy ???