in this video half the photons produce more growth due to better spectrum
the graph is from Columbia.plants have close to 400 pigments.this graph shows absorption for all of them. this belief is more bro-science plants can adapt to any form of light but provide better taste and potency with an SPD that LEDS and HPS can not produce some growers supplement these lights with UV bulbs with the right SPD plant can flower well with only 2500 lumens/sqft
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Your videos don't appear to dispute what I wrote. For a start, the UVB bulb could well be throwing out 3x the photons of the test bulb, but we will never know, because they used a standard PAR meter that does not read anything above or below 400-700nm.
Also, your reference to "2500 lumens per square foot" could mean anything when the spectra you are using is not weighted towards 550nm, where lumens peak, and may or may not fall outside the visible range, or may be weighted towards either end of the PAR range. I would count wavelengths outside 400-700nm in the PAR range, but that's another story.
I don't know if you're going to convince anyone that fluorescent bulbs can outperform LED. Their efficiency sucks and the only way to tune the spectrum is with phosphors.
Is that what you're trying to tell us? That fluoros are better than LED? Apologies if that is not what you are saying, but that's the way i read it.
BTW, LEDs can produce any spectrum fluoros can: it's just a matter of cost, efficiency and mixing the right LEDs. I guarantee those LEDs will last longer than those fluoro bulbs, too, which will start to degrade in performance almost from the time you turn them on.
We've done a bit of research into spectrum also, so note I am not saying spectrum is not important. And I didn't say PAR > spectrum – I said "photons > spectrum" and it is a generalised comment when talking about reasonably comparative lights. Obviously hitting plants with a high source of blue is likely to be more detrimental than hitting them with a lower does of full spectrum. It's about perspective.
