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I'm not saying you're wrong about it not being light burn, but comparing light intensity from sunlight to an artificial light probably isn't a good way to compare. In the sun, my plants are getting about 135,000+ lux. I don't think that's recommended by any lighting manufacturer.
Since the plants we now grow under artificial lights spent their history under sunlight I would think that is exactly what we would compare because that is what we are trying to imitate? But yes, par readings are a measurement of light but only of the spectrum used by plants so I understand it is sort of apples and oranges though from what Google says below I think they are in the ballpark.
My light meter, that reads in lux, cannot be converted to par, which is what all the manufacturers of grow lights quote in, according to Google absolutely accurately without knowing the light sources spectrum or frequency which leads one to believe that even without knowing the source spectrum it would be fairly accurate.
You got me curious with your inquiry so I checked the NextLight website for the specifications and (below) this is what they say about distances and I am at 24 inches so I am at the outer limits for distance in flower but also instead of giving my MegaLight the maximum 650 W it will take I am only giving it 200 W so I am giving less than one-third of the minimum recommended power so I really doubt it is leaf burn.
"PAR tells growers the wavelength or color of photosynthetic light, but to describe the photon energy or intensity of the light, another measure is needed. Photosynthetic photon flux density (PPFD) is expressed as μmol∙m-2∙s-1, which is micromoles per square meter per second. PPFD describes the number of energy particles (photons) in the photosynthetic active radiation (PAR) range that falls on a one square meter area in one second."
Here is the par chart for that light. The maximum par at 18 inches with no reflector is 718, so 718 times 200÷650 equals about 221 par which is the most my lights are giving my plants at 18" but I am at 24" so it is even lower.
I found this chart on another forum and if accurate my plants are definitely at the low end of light received at 221 PAR at 18" which I figure about 165 PAR at 24".
(24 hour on lighting)
250 PAR - Seedlings
450 PAR - teens up until around 9 inches of height (they should be ultra dense and bushy)
500 PAR - Switch to 12/12 lighting
750 PAR - Mid bloom
850 PAR - mid-late bloom
400 PAR - Last three weeks ( shade them in simulation )
So according to my light meter I am getting 1/8 of outdoor with my lights and about 1/5 of the recommendation of the manufacturer using their charts. I didn't realize it was so low but even at this illumination, I am getting pretty good yields so not sure I will change it as I like my $103 electric bills.