Calculating proper lighting…when distances change

[PeaceLove&Buds]

The 24” graph in the pic above is the reason I run 36-40” away. The farther my light the less dramatic drop in the corners as well as growth below the canopy. Like the sun.

 

[BII]

Using basically similar quantum boards, I simply start the lights at 100% at a meter/40-inches above media level and let the plants grow towards the light. I don't move the lights up or down, much less dial down the intensity.

I presume grow lights other than those that are point sources (such as single COBs), particularly quantum boards, provide better light penetration below the canopy, from more angles vs. the sun, a point source. The sun may simply provide seemingly better growth because it is often more intense than most grow lights(?).