But Nichia did actually state what diode they were using in those trials you had linked. They put the “conventional LED” 5000k (Ra>80CRI) on the spectral graph next to the Hortisolis chip to so that the reader has a visual understanding of the differences between the spectrum used in their trials.
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Now, I’m not so naive to assume that Nichia ONLY tested their Hortisolis spectrum against only a 5000k 80CRI chip for ALL of their research, nor did I imply that. But I can plainly see that the 5000k Conventional LED was used in the trials you originally linked as reference. I don’t know why you think Nichia would arbitrarily compare the spectrums of two diodes, and then do a bait and switch on control chips actually used to do the growing.
“Our objective was to quantify the effects of far-red substitution for 400–700 nm photons on radiation capture, canopy quantum yield, carbon use efficiency, and biomass allocation of a model crop lettuce.”
…from the Bugbee Study. No mention of trying to isolate Red from Far-Red, just “substituting” a certain flux level of 700-750nm wavelengths. Since we know the Emerson effect has to do with R: FR ratios, I’m dumbfounded as to why 660-700nm weren’t adequately covered in the white light experiments.
Far-red photons regulate shade avoidance responses and can have powerful effects on plant morphology and radiation capture. Recent studies have shown that far-red photons (700 to 750 nm) efficiently drive photosynthesis when added to traditionally ...
www.ncbi.nlm.nih.gov
I don’t have issues with the studies themselves. But extrapolating growth effects of Far-Red light would be somewhat foolhardy, considering the experiment parameters and control spectrum limitations.
I have experimented using supplemental Red, Far-Red, and UV in my grows dating as far back as 7 years ago. I also grew 3 different cuts under the enhanced spectra, as well as under 3500K (80CRI) Vero 29 chips only, because I had two different grow rooms to trial the lights. My results weren’t anything to write home about. Yield was less under the “enhanced” spectrum while including UV, but was similar when the Power VEG bulbs were swapped with standard 6500k T5 bulbs. Like you, I experienced similar yields between my experimental spectrum and the control spectrum and maybe a bit quicker ripening of buds by a few days. They seemed to pray a bit easier, which I contributed to the 660nm diodes, but end results couldn’t be really distinguished. I did these trials for a little over 2 years. I used an Apogee Quantum meter to ensure similar flux conditions, which means the “enhanced” spectrum had more photons that weren’t being measured by the light meter.
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I don’t doubt Far-Reds role or benefit in photosynthesis, but many make claims that a spectrum is inferior without having Far-Red in the spectrum. My question is how much is needed and what results should one expect? And then I’d say “prove that it’s better”