Measured a peak of 781lm turbo, and a floor of <1lm (as low as my tube’s luxmeter goes. I do have a different luxmeter with a higher precision but do not yet have a calibration factor for the tube with it. Eyeballing it, probably around 0.5lm or so, but this light does not currently have the latest firmware which should make the lows a bit lower.
Tested with a freshly charged Vapcell H10 and a 4.5 inch Texas Ace lumen tube - see @PetToilet’s reply; I would consider this level of equipment accurate to +/- 10% - to get significantly more precision than that costs several thousand dollars.
If you want me to do a 30s test or a full runtime test, let me know and I can tomorrow, but at the moment I am moving stuff around so I can’t currently use my tube for an extended time during the evening without disturbing my sleeping partner. I can also update the firmware and test again then as well.