light angle plays a role too. in summer/fall, the light isn't so much overhead as it is near the horizon. ever notice inder hps, some strains grow better on the perimeter of the tent/box/room? less light/ less direct light/and at an angle. something to think about. there's a reason mexican weed tastes and has a different cannabinoid profile than the same weed grown in kansas. as a matter of fact, i chose those 2 places because i read an article about how bud that's known to have no cbd in one place, can grw with cbd in another, kansas vs mexico. and the opposite is true. a strain known to have high cbd in one area, grown in another can have none. it's amazin, we know so little about it.