Great thread. I just got my light meter and I'll be measuring my Procyons soon, your measurements are an unexpected godsend - thank you. I'd rep you but I don't think I have enough posts for that

One thing I thought I'd mention is that when my Procyon gets closer than 24" to the canopy, the leaves twist sideways and "ram's horns" show up - like they're responding to heat stress. Which is relieved as soon as I move the light up.

I guess the lower lux # is due to it emitting only blue & red light and that the lux measurement totals for the HIDs include the other spectra(?) Hence my plants reacting as if they're receiving too much light when actually the lux reading is lower than what it would be with an HID b/c plants use more red and blue. I'm just stabbing around here. What do you think?