@organicchronic

P.S. if you want to reply to someone use your DM direct message inbox. Its the little paper airplane looking icon/tab on the bottom right of the website. You can search their name or just go to their profile and hit chat in the upper right of their profile page. Right beside the giant follow buttion.

That might be too much.. you really need an average over the entire canopy at many locations and same distance to calculate DLI. DLI is what matters. e.g. those numbers you list for 18 hour operation would likely cook plants. If using a phone app, you may be +/-15%. Those apps are good for evening out the light (i.e. distance hung from canopy). It doesn't have to be accurate, merely consistent in how it measures, and it can accomplish that feat. How intense it should be is guided by resulting growth of the plant, because numerous local variables impace just how much photosynthesis it can do per day. There is no single target to aim for. You must learn the target. if nodes are too tight, need less. if too stretchy, need more. Hopefully you can control that with a dimmer and allow the distance you hang from canopy provide the best light coverage wall to wall without sacrificing overall average too much, if at all. Based on your measurements, i don't expect much tweaking. It's usually a bit too much in center and a similar drop off at walls/edges as you have. Keep any eye out for tight nodes. You may need an extra inch of height or 5-10% less power etc. sometimes it takes a long time to see damage. e.g. in flower you may be giving too much, but it'll takes weeks before you see a burned pistil or a bleached bud. the longer it takes to cause a visible symptom, the less you need to adjust. if you want to be wasteful and have a little extra power, raise light higher, amp it up, and you'll get a bit better light penetration deeper into canopy. This has to do with how light spreads out over incremental distances according to the inverse square law. Not saying it is economically worth it, but will have a positive effect of some sort.