Wurkkos TS30S + monster LED SBT90.2 = $60 4750lm 1km SUPER-Thrower. Comparison w/ TS30S Pro & world's brightest single LED light NW Valkyrie, and NOW! *Firefly T9R w/ FFL909MX*. (Summary & measurements on P. 1)

[cannga]

Thanks. I googled and found a discussion on corona here Some noob flashaholic question about the flashlight's beam anatomy, which refers to this LED optics in Flashlight, which re-states what you’ve been discussing.

Here are the 2 slides on corona (“coma” on the slide):