GTR Ultra 3 vs F3S Pro. Which is brighter?

Here is a bit of data for those of you who believe the GTR Ultra 3 TST is brighter than the F3S Pro.

Independent tests show the GTR Ultra 3 measured lumen to be around 4700 per bulb as reported by Google AI -> "The GTR Lighting Ultra 3 H11 LED bulb provides around 4,700 raw lumens per bulb, with independent tests measuring around 4,788 lumens" -> REFERENCE LINK

The F3S Pro consistenly tested at 8400lm per bulb, 83.6W, and 14.04Amps on start-up. As the F3S Pro bulb temperature increased the lumen output decreased and stabilized at 6878lm (after approximately 5 minute run time), still making it brighter than the GTR Ultra 3, which also likely shows a runtime lumen output decrease over time, but it's not being reported. See actual lumen test photo below.

How much brighter is the F3S Pro?

Step 1: Find the difference in lumens
8400 − 4700 = 3700 lumens

Step 2: Divide the difference by the original value (4700)
3700 ÷ 4700 ≈ 0.787

Step 3: Convert to percentage
0.787 × 100 ≈ 78.7%

Final answer: The 8400 lumen F3S Pro bulb is about 79% brighter than the 4700 lumen GTR Ultra 3 bulb, or roughly 1.8× brighter.

More over TST (Thermal Separation Technology) has not shown increased brightness. TST excels at improving LED beam pattern, having thinner bulb shadow, and offering better heat dissipation over the standard copper plate diode mouting. 

I am not here to convert anyone, believe what you want to believe. I am just presenting actual test data for education purposes.

In summary, the F3S Pro IS brighter than the GTR Ultra 3 TST.