Yes, I have a TA tube and am in Houston. Maukka is in Finland, though.
Why not send it to Texas_Ace? He is just north of you near Dallas and he has the lights that Maukka measured for him plus his reference tube which mine was built from. So he can do a more accurate comparison.
You might even send a cheap light to measure as long as it’s output is stable. The D1s, being a FET driver, is going to fluctuate based on voltage. It may not be the best choice for steady output.
It would be cool if you guys collaborate.
I do plan to start a thread on the different integrating spheres, just not right now. I will mention that TA’s tube differs from most in that it uses 3 diffusers to help collimate the light and give better accuracy between throwy lights and floody lights. Here is the thread on them. Texas_Ace BLF Calibrated Lumen tube / Sphere No math skills needed - Several spheres still available
In fact, I think he has a few left for sale if anyone wants to buy one.
Here is the TA Lumen Tube.
TA adds reflective tape in certain areas to get the meter both calibrated and to have the lux readout on the meter be the actual lumens! No math involved. We are still working on that last part. Right now we all have to use math to multiply the readout by .68. This is being fixed, though.