I was not guessing at all. You assume this. I was reading the data right off of Koef3’s chart.
If we took the losses from your ODL 20C which measure 22% and apply it to the 4.5A 1500 lumen measurement we get 1170. So Lumintops GT Mini rating of 1200 lumen does sound about right. I’m sure there will some versions of the Mini that read 1100 lumen and some will read higher. It’s all around the right range. Time will tell.
For the record, when I first got this Lumintop built up I used a Liito Kala 5000mAh Black 26650. It did 6.49A at the tail for 1745 lumens at start. Follow that on Koef3’s chart… count the losses.
With all that has been said between Dale and JasonWW I see that it is in agreement (basically) that the XP-L HI IN A FLASHLIGHT will be doing around 1200 lumens at 4.5 amps.
With the steady current bench power supply , that is all great to see just what current an emitter MIGHT handle , but it tells us nothing of what the emitter will do in a flashlight of any kind that I can see.
When using the bench power supply and heat sinking it with a chunk of copper or aluminum and a fan to cool the emitter , then I do not see where that will any where near replicate “real world” use in a light.
With the XP-L HI in the lights I have modded , I would say an average of 1050 to 1250 lumens is about where the mini GT and most other lights will be as a guess from prior experences with the 4.5 amps. Of course it will depend on ALL those varibles of what type springs , the cell used , other resistance points and so on , as to the final output.