Can You Guys Help a Noob Optimize Distance and Wattage? CXB3590's 3500k

I have a flower room that has 16 CXB3590s powered by 4 drivers @1.4A

I have the drivers dialed so that every COB is currently getting about 45 watts each.

My COBs are arranged with 4 COBs over each plant and I have 4 plants, each plant takes up about 5 to 6 sq. ft. footprint and are about 20 inches away from my SCROG canopy at the moment. Here are photos of my lighting above a couple of my plants:







I have a lux meter and I'm currently averaging roughly 45k LUX in the middle of my canopy with the edges around 30k.

I understand a quantum meter would serve my intents and purposes much better but it is out of my budget.

I recently had one of four plants go hermie on me and since then i am trying to make sure all parameters in my room are A-okay. With that being said, is there a way for me to optimize my lighting without a quantum meter? Can you guys somehow show me how i can optimize my lighting without a quantum meter so i can heave peace of mind? I am not sure if there is a specific PPFD or PAR i should be aiming for and if there is, can you guys help me determine those measurements without a quantum meter?

I'm really not sure if i'm wasting electricity or if my lights are too close or far away given the intensity of my lighting. Any way to use a quantum meter to get a ballpark figure of something more specific?

I would appreciate any help I can get on the subject!

20" is to far away I think.
12" to 15" in flower I would say.
You are wasting too much light on the walls rather than directly hitting plants.
When I tested with par meter under the 5 x cxbs at 160 watts at wall it gives a reading of circa 1000 umols at around 12 - 15 inches away. - I've other lights in there too.
Same sorta measurement with 4 x cxb at 200 wall watts in 80cm x 80cm at around 12-ish inches away.
900 with par meter at top of canopy.
I hope that helps